Update clang, llvm, lld, lldb, compiler-rt and libc++ to 4.0.0 release:

MFC r309142 (by emaste):

Add WITH_LLD_AS_LD build knob

If set it installs LLD as /usr/bin/ld.  LLD (as of version 3.9) is not
capable of linking the world and kernel, but can self-host and link many
substantial applications. GNU ld continues to be used for the world and
kernel build, regardless of how this knob is set.

It is on by default for arm64, and off for all other CPU architectures.

Sponsored by:	The FreeBSD Foundation

MFC r310840:

Reapply 310775, now it also builds correctly if lldb is disabled:

Move llvm-objdump from CLANG_EXTRAS to installed by default

We currently install three tools from binutils 2.17.50: as, ld, and
objdump. Work is underway to migrate to a permissively-licensed
tool-chain, with one goal being the retirement of binutils 2.17.50.

LLVM's llvm-objdump is intended to be compatible with GNU objdump
although it is currently missing some options and may have formatting
differences. Enable it by default for testing and further investigation.
It may later be changed to install as /usr/bin/objdump, it becomes a
fully viable replacement.

Reviewed by:	emaste
Differential Revision:	https://reviews.freebsd.org/D8879

MFC r312855 (by emaste):

Rename LLD_AS_LD to LLD_IS_LD, for consistency with CLANG_IS_CC

Reported by:	Dan McGregor <dan.mcgregor usask.ca>

MFC r313559 | glebius | 2017-02-10 18:34:48 +0100 (Fri, 10 Feb 2017) | 5 lines

Don't check struct rtentry on FreeBSD, it is an internal kernel structure.
On other systems it may be API structure for SIOCADDRT/SIOCDELRT.

Reviewed by:	emaste, dim

MFC r314152 (by jkim):

Remove an assembler flag, which is redundant since r309124.  The upstream
took care of it by introducing a macro NO_EXEC_STACK_DIRECTIVE.

http://llvm.org/viewvc/llvm-project?rev=273500&view=rev

Reviewed by:	dim

MFC r314564:

Upgrade our copies of clang, llvm, lld, lldb, compiler-rt and libc++ to
4.0.0 (branches/release_40 296509).  The release will follow soon.

Please note that from 3.5.0 onwards, clang, llvm and lldb require C++11
support to build; see UPDATING for more information.

Also note that as of 4.0.0, lld should be able to link the base system
on amd64 and aarch64.  See the WITH_LLD_IS_LLD setting in src.conf(5).
Though please be aware that this is work in progress.

Release notes for llvm, clang and lld will be available here:
<http://releases.llvm.org/4.0.0/docs/ReleaseNotes.html>
<http://releases.llvm.org/4.0.0/tools/clang/docs/ReleaseNotes.html>
<http://releases.llvm.org/4.0.0/tools/lld/docs/ReleaseNotes.html>

Thanks to Ed Maste, Jan Beich, Antoine Brodin and Eric Fiselier for
their help.

Relnotes:	yes
Exp-run:	antoine
PR:		215969, 216008

MFC r314708:

For now, revert r287232 from upstream llvm trunk (by Daniil Fukalov):

  [SCEV] limit recursion depth of CompareSCEVComplexity

  Summary:
  CompareSCEVComplexity goes too deep (50+ on a quite a big unrolled
  loop) and runs almost infinite time.

  Added cache of "equal" SCEV pairs to earlier cutoff of further
  estimation. Recursion depth limit was also introduced as a parameter.

  Reviewers: sanjoy

  Subscribers: mzolotukhin, tstellarAMD, llvm-commits

  Differential Revision: https://reviews.llvm.org/D26389

This commit is the cause of excessive compile times on skein_block.c
(and possibly other files) during kernel builds on amd64.

We never saw the problematic behavior described in this upstream commit,
so for now it is better to revert it.  An upstream bug has been filed
here: https://bugs.llvm.org/show_bug.cgi?id=32142

Reported by:	mjg

MFC r314795:

Reapply r287232 from upstream llvm trunk (by Daniil Fukalov):

  [SCEV] limit recursion depth of CompareSCEVComplexity

  Summary:
  CompareSCEVComplexity goes too deep (50+ on a quite a big unrolled
  loop) and runs almost infinite time.

  Added cache of "equal" SCEV pairs to earlier cutoff of further
  estimation. Recursion depth limit was also introduced as a parameter.

  Reviewers: sanjoy

  Subscribers: mzolotukhin, tstellarAMD, llvm-commits

  Differential Revision: https://reviews.llvm.org/D26389

Pull in r296992 from upstream llvm trunk (by Sanjoy Das):

  [SCEV] Decrease the recursion threshold for CompareValueComplexity

  Fixes PR32142.

  r287232 accidentally increased the recursion threshold for
  CompareValueComplexity from 2 to 32.  This change reverses that
  change by introducing a separate flag for CompareValueComplexity's
  threshold.

The latter revision fixes the excessive compile times for skein_block.c.

MFC r314907 | mmel | 2017-03-08 12:40:27 +0100 (Wed, 08 Mar 2017) | 7 lines

Unbreak ARMv6 world.

The new compiler_rt library imported with clang 4.0.0 have several fatal
issues (non-functional __udivsi3 for example) with ARM specific instrict
functions. As temporary workaround, until upstream solve these problems,
disable all thumb[1][2] related feature.

MFC r315016:

Update clang, llvm, lld, lldb, compiler-rt and libc++ to 4.0.0 release.
We were already very close to the last release candidate, so this is a
pretty minor update.

Relnotes:	yes

MFC r316005:

Revert r314907, and pull in r298713 from upstream compiler-rt trunk (by
Weiming Zhao):

  builtins: Select correct code fragments when compiling for Thumb1/Thum2/ARM ISA.

  Summary:
  Value of __ARM_ARCH_ISA_THUMB isn't based on the actual compilation
  mode (-mthumb, -marm), it reflect's capability of given CPU.

  Due to this:
   - use  __tbumb__ and __thumb2__ insteand of __ARM_ARCH_ISA_THUMB
   - use '.thumb' directive consistently  in all affected files
   - decorate all thumb functions using
     DEFINE_COMPILERRT_THUMB_FUNCTION()

  ---------
  Note: This patch doesn't fix broken Thumb1 variant of __udivsi3 !

  Reviewers: weimingz, rengolin, compnerd

  Subscribers: aemerson, dim

  Differential Revision: https://reviews.llvm.org/D30938

Discussed with:	mmel

1 files changed, 4276 insertions, 0 deletions

diff --git a/contrib/llvm/lib/Demangle/ItaniumDemangle.cpp b/contrib/llvm/lib/Demangle/ItaniumDemangle.cpp
new file mode 100644
index 0000000..097b6ca
--- /dev/null
+++ b/contrib/llvm/lib/Demangle/ItaniumDemangle.cpp
@@ -0,0 +1,4276 @@
+//===- ItaniumDemangle.cpp ------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Demangle/Demangle.h"
+
+// This file exports a single function: llvm::itanium_demangle.
+// It also has no dependencies on the rest of llvm. It is implemented this way
+// so that it can be easily reused in libcxxabi.
+
+#include <algorithm>
+#include <cctype>
+#include <cstdlib>
+#include <cstring>
+#include <numeric>
+#include <string>
+#include <vector>
+
+#ifdef _MSC_VER
+// snprintf is implemented in VS 2015
+#if _MSC_VER < 1900
+#define snprintf _snprintf_s
+#endif
+#endif
+
+enum {
+  unknown_error = -4,
+  invalid_args = -3,
+  invalid_mangled_name,
+  memory_alloc_failure,
+  success
+};
+
+template <class C>
+static const char *parse_type(const char *first, const char *last, C &db);
+template <class C>
+static const char *parse_encoding(const char *first, const char *last, C &db);
+template <class C>
+static const char *parse_name(const char *first, const char *last, C &db,
+                              bool *ends_with_template_args = 0);
+template <class C>
+static const char *parse_expression(const char *first, const char *last, C &db);
+template <class C>
+static const char *parse_template_args(const char *first, const char *last,
+                                       C &db);
+template <class C>
+static const char *parse_operator_name(const char *first, const char *last,
+                                       C &db);
+template <class C>
+static const char *parse_unqualified_name(const char *first, const char *last,
+                                          C &db);
+template <class C>
+static const char *parse_decltype(const char *first, const char *last, C &db);
+
+// <number> ::= [n] <non-negative decimal integer>
+
+static const char *parse_number(const char *first, const char *last) {
+  if (first != last) {
+    const char *t = first;
+    if (*t == 'n')
+      ++t;
+    if (t != last) {
+      if (*t == '0') {
+        first = t + 1;
+      } else if ('1' <= *t && *t <= '9') {
+        first = t + 1;
+        while (first != last && std::isdigit(*first))
+          ++first;
+      }
+    }
+  }
+  return first;
+}
+
+namespace {
+template <class Float> struct float_data;
+
+template <> struct float_data<float> {
+  static const size_t mangled_size = 8;
+  static const size_t max_demangled_size = 24;
+  static const char *spec;
+};
+const char *float_data<float>::spec = "%af";
+
+template <> struct float_data<double> {
+  static const size_t mangled_size = 16;
+  static const size_t max_demangled_size = 32;
+  static const char *spec;
+};
+
+const char *float_data<double>::spec = "%a";
+
+template <> struct float_data<long double> {
+#if defined(__mips__) && defined(__mips_n64) || defined(__aarch64__) ||        \
+    defined(__wasm__)
+  static const size_t mangled_size = 32;
+#elif defined(__arm__) || defined(__mips__) || defined(__hexagon__)
+  static const size_t mangled_size = 16;
+#else
+  static const size_t mangled_size =
+      20; // May need to be adjusted to 16 or 24 on other platforms
+#endif
+  static const size_t max_demangled_size = 40;
+  static const char *spec;
+};
+
+const char *float_data<long double>::spec = "%LaL";
+}
+
+template <class Float, class C>
+static const char *parse_floating_number(const char *first, const char *last,
+                                         C &db) {
+  const size_t N = float_data<Float>::mangled_size;
+  if (static_cast<std::size_t>(last - first) > N) {
+    last = first + N;
+    union {
+      Float value;
+      char buf[sizeof(Float)];
+    };
+    const char *t = first;
+    char *e = buf;
+    for (; t != last; ++t, ++e) {
+      if (!isxdigit(*t))
+        return first;
+      unsigned d1 = isdigit(*t) ? static_cast<unsigned>(*t - '0')
+                                : static_cast<unsigned>(*t - 'a' + 10);
+      ++t;
+      unsigned d0 = isdigit(*t) ? static_cast<unsigned>(*t - '0')
+                                : static_cast<unsigned>(*t - 'a' + 10);
+      *e = static_cast<char>((d1 << 4) + d0);
+    }
+    if (*t == 'E') {
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+      std::reverse(buf, e);
+#endif
+      char num[float_data<Float>::max_demangled_size] = {0};
+      int n = snprintf(num, sizeof(num), float_data<Float>::spec, value);
+      if (static_cast<std::size_t>(n) >= sizeof(num))
+        return first;
+      db.names.push_back(std::string(num, static_cast<std::size_t>(n)));
+      first = t + 1;
+    }
+  }
+  return first;
+}
+
+// <source-name> ::= <positive length number> <identifier>
+
+template <class C>
+static const char *parse_source_name(const char *first, const char *last,
+                                     C &db) {
+  if (first != last) {
+    char c = *first;
+    if (isdigit(c) && first + 1 != last) {
+      const char *t = first + 1;
+      size_t n = static_cast<size_t>(c - '0');
+      for (c = *t; isdigit(c); c = *t) {
+        n = n * 10 + static_cast<size_t>(c - '0');
+        if (++t == last)
+          return first;
+      }
+      if (static_cast<size_t>(last - t) >= n) {
+        std::string r(t, n);
+        if (r.substr(0, 10) == "_GLOBAL__N")
+          db.names.push_back("(anonymous namespace)");
+        else
+          db.names.push_back(std::move(r));
+        first = t + n;
+      }
+    }
+  }
+  return first;
+}
+
+// <substitution> ::= S <seq-id> _
+//                ::= S_
+// <substitution> ::= Sa # ::std::allocator
+// <substitution> ::= Sb # ::std::basic_string
+// <substitution> ::= Ss # ::std::basic_string < char,
+//                                               ::std::char_traits<char>,
+//                                               ::std::allocator<char> >
+// <substitution> ::= Si # ::std::basic_istream<char,  std::char_traits<char> >
+// <substitution> ::= So # ::std::basic_ostream<char,  std::char_traits<char> >
+// <substitution> ::= Sd # ::std::basic_iostream<char, std::char_traits<char> >
+
+template <class C>
+static const char *parse_substitution(const char *first, const char *last,
+                                      C &db) {
+  if (last - first >= 2) {
+    if (*first == 'S') {
+      switch (first[1]) {
+      case 'a':
+        db.names.push_back("std::allocator");
+        first += 2;
+        break;
+      case 'b':
+        db.names.push_back("std::basic_string");
+        first += 2;
+        break;
+      case 's':
+        db.names.push_back("std::string");
+        first += 2;
+        break;
+      case 'i':
+        db.names.push_back("std::istream");
+        first += 2;
+        break;
+      case 'o':
+        db.names.push_back("std::ostream");
+        first += 2;
+        break;
+      case 'd':
+        db.names.push_back("std::iostream");
+        first += 2;
+        break;
+      case '_':
+        if (!db.subs.empty()) {
+          for (const auto &n : db.subs.front())
+            db.names.push_back(n);
+          first += 2;
+        }
+        break;
+      default:
+        if (std::isdigit(first[1]) || std::isupper(first[1])) {
+          size_t sub = 0;
+          const char *t = first + 1;
+          if (std::isdigit(*t))
+            sub = static_cast<size_t>(*t - '0');
+          else
+            sub = static_cast<size_t>(*t - 'A') + 10;
+          for (++t; t != last && (std::isdigit(*t) || std::isupper(*t)); ++t) {
+            sub *= 36;
+            if (std::isdigit(*t))
+              sub += static_cast<size_t>(*t - '0');
+            else
+              sub += static_cast<size_t>(*t - 'A') + 10;
+          }
+          if (t == last || *t != '_')
+            return first;
+          ++sub;
+          if (sub < db.subs.size()) {
+            for (const auto &n : db.subs[sub])
+              db.names.push_back(n);
+            first = t + 1;
+          }
+        }
+        break;
+      }
+    }
+  }
+  return first;
+}
+
+// <builtin-type> ::= v    # void
+//                ::= w    # wchar_t
+//                ::= b    # bool
+//                ::= c    # char
+//                ::= a    # signed char
+//                ::= h    # unsigned char
+//                ::= s    # short
+//                ::= t    # unsigned short
+//                ::= i    # int
+//                ::= j    # unsigned int
+//                ::= l    # long
+//                ::= m    # unsigned long
+//                ::= x    # long long, __int64
+//                ::= y    # unsigned long long, __int64
+//                ::= n    # __int128
+//                ::= o    # unsigned __int128
+//                ::= f    # float
+//                ::= d    # double
+//                ::= e    # long double, __float80
+//                ::= g    # __float128
+//                ::= z    # ellipsis
+//                ::= Dd   # IEEE 754r decimal floating point (64 bits)
+//                ::= De   # IEEE 754r decimal floating point (128 bits)
+//                ::= Df   # IEEE 754r decimal floating point (32 bits)
+//                ::= Dh   # IEEE 754r half-precision floating point (16 bits)
+//                ::= Di   # char32_t
+//                ::= Ds   # char16_t
+//                ::= Da   # auto (in dependent new-expressions)
+//                ::= Dc   # decltype(auto)
+//                ::= Dn   # std::nullptr_t (i.e., decltype(nullptr))
+//                ::= u <source-name>    # vendor extended type
+
+template <class C>
+static const char *parse_builtin_type(const char *first, const char *last,
+                                      C &db) {
+  if (first != last) {
+    switch (*first) {
+    case 'v':
+      db.names.push_back("void");
+      ++first;
+      break;
+    case 'w':
+      db.names.push_back("wchar_t");
+      ++first;
+      break;
+    case 'b':
+      db.names.push_back("bool");
+      ++first;
+      break;
+    case 'c':
+      db.names.push_back("char");
+      ++first;
+      break;
+    case 'a':
+      db.names.push_back("signed char");
+      ++first;
+      break;
+    case 'h':
+      db.names.push_back("unsigned char");
+      ++first;
+      break;
+    case 's':
+      db.names.push_back("short");
+      ++first;
+      break;
+    case 't':
+      db.names.push_back("unsigned short");
+      ++first;
+      break;
+    case 'i':
+      db.names.push_back("int");
+      ++first;
+      break;
+    case 'j':
+      db.names.push_back("unsigned int");
+      ++first;
+      break;
+    case 'l':
+      db.names.push_back("long");
+      ++first;
+      break;
+    case 'm':
+      db.names.push_back("unsigned long");
+      ++first;
+      break;
+    case 'x':
+      db.names.push_back("long long");
+      ++first;
+      break;
+    case 'y':
+      db.names.push_back("unsigned long long");
+      ++first;
+      break;
+    case 'n':
+      db.names.push_back("__int128");
+      ++first;
+      break;
+    case 'o':
+      db.names.push_back("unsigned __int128");
+      ++first;
+      break;
+    case 'f':
+      db.names.push_back("float");
+      ++first;
+      break;
+    case 'd':
+      db.names.push_back("double");
+      ++first;
+      break;
+    case 'e':
+      db.names.push_back("long double");
+      ++first;
+      break;
+    case 'g':
+      db.names.push_back("__float128");
+      ++first;
+      break;
+    case 'z':
+      db.names.push_back("...");
+      ++first;
+      break;
+    case 'u': {
+      const char *t = parse_source_name(first + 1, last, db);
+      if (t != first + 1)
+        first = t;
+    } break;
+    case 'D':
+      if (first + 1 != last) {
+        switch (first[1]) {
+        case 'd':
+          db.names.push_back("decimal64");
+          first += 2;
+          break;
+        case 'e':
+          db.names.push_back("decimal128");
+          first += 2;
+          break;
+        case 'f':
+          db.names.push_back("decimal32");
+          first += 2;
+          break;
+        case 'h':
+          db.names.push_back("decimal16");
+          first += 2;
+          break;
+        case 'i':
+          db.names.push_back("char32_t");
+          first += 2;
+          break;
+        case 's':
+          db.names.push_back("char16_t");
+          first += 2;
+          break;
+        case 'a':
+          db.names.push_back("auto");
+          first += 2;
+          break;
+        case 'c':
+          db.names.push_back("decltype(auto)");
+          first += 2;
+          break;
+        case 'n':
+          db.names.push_back("std::nullptr_t");
+          first += 2;
+          break;
+        }
+      }
+      break;
+    }
+  }
+  return first;
+}
+
+// <CV-qualifiers> ::= [r] [V] [K]
+
+static const char *parse_cv_qualifiers(const char *first, const char *last,
+                                       unsigned &cv) {
+  cv = 0;
+  if (first != last) {
+    if (*first == 'r') {
+      cv |= 4;
+      ++first;
+    }
+    if (*first == 'V') {
+      cv |= 2;
+      ++first;
+    }
+    if (*first == 'K') {
+      cv |= 1;
+      ++first;
+    }
+  }
+  return first;
+}
+
+// <template-param> ::= T_    # first template parameter
+//                  ::= T <parameter-2 non-negative number> _
+
+template <class C>
+static const char *parse_template_param(const char *first, const char *last,
+                                        C &db) {
+  if (last - first >= 2) {
+    if (*first == 'T') {
+      if (first[1] == '_') {
+        if (db.template_param.empty())
+          return first;
+        if (!db.template_param.back().empty()) {
+          for (auto &t : db.template_param.back().front())
+            db.names.push_back(t);
+          first += 2;
+        } else {
+          db.names.push_back("T_");
+          first += 2;
+          db.fix_forward_references = true;
+        }
+      } else if (isdigit(first[1])) {
+        const char *t = first + 1;
+        size_t sub = static_cast<size_t>(*t - '0');
+        for (++t; t != last && isdigit(*t); ++t) {
+          sub *= 10;
+          sub += static_cast<size_t>(*t - '0');
+        }
+        if (t == last || *t != '_' || db.template_param.empty())
+          return first;
+        ++sub;
+        if (sub < db.template_param.back().size()) {
+          for (auto &temp : db.template_param.back()[sub])
+            db.names.push_back(temp);
+          first = t + 1;
+        } else {
+          db.names.push_back(std::string(first, t + 1));
+          first = t + 1;
+          db.fix_forward_references = true;
+        }
+      }
+    }
+  }
+  return first;
+}
+
+// cc <type> <expression>                               # const_cast<type>
+// (expression)
+
+template <class C>
+static const char *parse_const_cast_expr(const char *first, const char *last,
+                                         C &db) {
+  if (last - first >= 3 && first[0] == 'c' && first[1] == 'c') {
+    const char *t = parse_type(first + 2, last, db);
+    if (t != first + 2) {
+      const char *t1 = parse_expression(t, last, db);
+      if (t1 != t) {
+        if (db.names.size() < 2)
+          return first;
+        auto expr = db.names.back().move_full();
+        db.names.pop_back();
+        if (db.names.empty())
+          return first;
+        db.names.back() =
+            "const_cast<" + db.names.back().move_full() + ">(" + expr + ")";
+        first = t1;
+      }
+    }
+  }
+  return first;
+}
+
+// dc <type> <expression>                               # dynamic_cast<type>
+// (expression)
+
+template <class C>
+static const char *parse_dynamic_cast_expr(const char *first, const char *last,
+                                           C &db) {
+  if (last - first >= 3 && first[0] == 'd' && first[1] == 'c') {
+    const char *t = parse_type(first + 2, last, db);
+    if (t != first + 2) {
+      const char *t1 = parse_expression(t, last, db);
+      if (t1 != t) {
+        if (db.names.size() < 2)
+          return first;
+        auto expr = db.names.back().move_full();
+        db.names.pop_back();
+        if (db.names.empty())
+          return first;
+        db.names.back() =
+            "dynamic_cast<" + db.names.back().move_full() + ">(" + expr + ")";
+        first = t1;
+      }
+    }
+  }
+  return first;
+}
+
+// rc <type> <expression>                               # reinterpret_cast<type>
+// (expression)
+
+template <class C>
+static const char *parse_reinterpret_cast_expr(const char *first,
+                                               const char *last, C &db) {
+  if (last - first >= 3 && first[0] == 'r' && first[1] == 'c') {
+    const char *t = parse_type(first + 2, last, db);
+    if (t != first + 2) {
+      const char *t1 = parse_expression(t, last, db);
+      if (t1 != t) {
+        if (db.names.size() < 2)
+          return first;
+        auto expr = db.names.back().move_full();
+        db.names.pop_back();
+        if (db.names.empty())
+          return first;
+        db.names.back() = "reinterpret_cast<" + db.names.back().move_full() +
+                          ">(" + expr + ")";
+        first = t1;
+      }
+    }
+  }
+  return first;
+}
+
+// sc <type> <expression>                               # static_cast<type>
+// (expression)
+
+template <class C>
+static const char *parse_static_cast_expr(const char *first, const char *last,
+                                          C &db) {
+  if (last - first >= 3 && first[0] == 's' && first[1] == 'c') {
+    const char *t = parse_type(first + 2, last, db);
+    if (t != first + 2) {
+      const char *t1 = parse_expression(t, last, db);
+      if (t1 != t) {
+        if (db.names.size() < 2)
+          return first;
+        auto expr = db.names.back().move_full();
+        db.names.pop_back();
+        db.names.back() =
+            "static_cast<" + db.names.back().move_full() + ">(" + expr + ")";
+        first = t1;
+      }
+    }
+  }
+  return first;
+}
+
+// sp <expression>                                  # pack expansion
+
+template <class C>
+static const char *parse_pack_expansion(const char *first, const char *last,
+                                        C &db) {
+  if (last - first >= 3 && first[0] == 's' && first[1] == 'p') {
+    const char *t = parse_expression(first + 2, last, db);
+    if (t != first + 2)
+      first = t;
+  }
+  return first;
+}
+
+// st <type>                                            # sizeof (a type)
+
+template <class C>
+static const char *parse_sizeof_type_expr(const char *first, const char *last,
+                                          C &db) {
+  if (last - first >= 3 && first[0] == 's' && first[1] == 't') {
+    const char *t = parse_type(first + 2, last, db);
+    if (t != first + 2) {
+      if (db.names.empty())
+        return first;
+      db.names.back() = "sizeof (" + db.names.back().move_full() + ")";
+      first = t;
+    }
+  }
+  return first;
+}
+
+// sz <expr>                                            # sizeof (a expression)
+
+template <class C>
+static const char *parse_sizeof_expr_expr(const char *first, const char *last,
+                                          C &db) {
+  if (last - first >= 3 && first[0] == 's' && first[1] == 'z') {
+    const char *t = parse_expression(first + 2, last, db);
+    if (t != first + 2) {
+      if (db.names.empty())
+        return first;
+      db.names.back() = "sizeof (" + db.names.back().move_full() + ")";
+      first = t;
+    }
+  }
+  return first;
+}
+
+// sZ <template-param>                                  # size of a parameter
+// pack
+
+template <class C>
+static const char *parse_sizeof_param_pack_expr(const char *first,
+                                                const char *last, C &db) {
+  if (last - first >= 3 && first[0] == 's' && first[1] == 'Z' &&
+      first[2] == 'T') {
+    size_t k0 = db.names.size();
+    const char *t = parse_template_param(first + 2, last, db);
+    size_t k1 = db.names.size();
+    if (t != first + 2) {
+      std::string tmp("sizeof...(");
+      size_t k = k0;
+      if (k != k1) {
+        tmp += db.names[k].move_full();
+        for (++k; k != k1; ++k)
+          tmp += ", " + db.names[k].move_full();
+      }
+      tmp += ")";
+      for (; k1 != k0; --k1)
+        db.names.pop_back();
+      db.names.push_back(std::move(tmp));
+      first = t;
+    }
+  }
+  return first;
+}
+
+// <function-param> ::= fp <top-level CV-qualifiers> _ # L == 0, first parameter
+//                  ::= fp <top-level CV-qualifiers> <parameter-2 non-negative
+//                  number> _   # L == 0, second and later parameters
+//                  ::= fL <L-1 non-negative number> p <top-level CV-qualifiers>
+//                  _         # L > 0, first parameter
+//                  ::= fL <L-1 non-negative number> p <top-level CV-qualifiers>
+//                  <parameter-2 non-negative number> _   # L > 0, second and
+//                  later parameters
+
+template <class C>
+static const char *parse_function_param(const char *first, const char *last,
+                                        C &db) {
+  if (last - first >= 3 && *first == 'f') {
+    if (first[1] == 'p') {
+      unsigned cv;
+      const char *t = parse_cv_qualifiers(first + 2, last, cv);
+      const char *t1 = parse_number(t, last);
+      if (t1 != last && *t1 == '_') {
+        db.names.push_back("fp" + std::string(t, t1));
+        first = t1 + 1;
+      }
+    } else if (first[1] == 'L') {
+      unsigned cv;
+      const char *t0 = parse_number(first + 2, last);
+      if (t0 != last && *t0 == 'p') {
+        ++t0;
+        const char *t = parse_cv_qualifiers(t0, last, cv);
+        const char *t1 = parse_number(t, last);
+        if (t1 != last && *t1 == '_') {
+          db.names.push_back("fp" + std::string(t, t1));
+          first = t1 + 1;
+        }
+      }
+    }
+  }
+  return first;
+}
+
+// sZ <function-param>                                  # size of a function
+// parameter pack
+
+template <class C>
+static const char *parse_sizeof_function_param_pack_expr(const char *first,
+                                                         const char *last,
+                                                         C &db) {
+  if (last - first >= 3 && first[0] == 's' && first[1] == 'Z' &&
+      first[2] == 'f') {
+    const char *t = parse_function_param(first + 2, last, db);
+    if (t != first + 2) {
+      if (db.names.empty())
+        return first;
+      db.names.back() = "sizeof...(" + db.names.back().move_full() + ")";
+      first = t;
+    }
+  }
+  return first;
+}
+
+// te <expression>                                      # typeid (expression)
+// ti <type>                                            # typeid (type)
+
+template <class C>
+static const char *parse_typeid_expr(const char *first, const char *last,
+                                     C &db) {
+  if (last - first >= 3 && first[0] == 't' &&
+      (first[1] == 'e' || first[1] == 'i')) {
+    const char *t;
+    if (first[1] == 'e')
+      t = parse_expression(first + 2, last, db);
+    else
+      t = parse_type(first + 2, last, db);
+    if (t != first + 2) {
+      if (db.names.empty())
+        return first;
+      db.names.back() = "typeid(" + db.names.back().move_full() + ")";
+      first = t;
+    }
+  }
+  return first;
+}
+
+// tw <expression>                                      # throw expression
+
+template <class C>
+static const char *parse_throw_expr(const char *first, const char *last,
+                                    C &db) {
+  if (last - first >= 3 && first[0] == 't' && first[1] == 'w') {
+    const char *t = parse_expression(first + 2, last, db);
+    if (t != first + 2) {
+      if (db.names.empty())
+        return first;
+      db.names.back() = "throw " + db.names.back().move_full();
+      first = t;
+    }
+  }
+  return first;
+}
+
+// ds <expression> <expression>                         # expr.*expr
+
+template <class C>
+static const char *parse_dot_star_expr(const char *first, const char *last,
+                                       C &db) {
+  if (last - first >= 3 && first[0] == 'd' && first[1] == 's') {
+    const char *t = parse_expression(first + 2, last, db);
+    if (t != first + 2) {
+      const char *t1 = parse_expression(t, last, db);
+      if (t1 != t) {
+        if (db.names.size() < 2)
+          return first;
+        auto expr = db.names.back().move_full();
+        db.names.pop_back();
+        db.names.back().first += ".*" + expr;
+        first = t1;
+      }
+    }
+  }
+  return first;
+}
+
+// <simple-id> ::= <source-name> [ <template-args> ]
+
+template <class C>
+static const char *parse_simple_id(const char *first, const char *last, C &db) {
+  if (first != last) {
+    const char *t = parse_source_name(first, last, db);
+    if (t != first) {
+      const char *t1 = parse_template_args(t, last, db);
+      if (t1 != t) {
+        if (db.names.size() < 2)
+          return first;
+        auto args = db.names.back().move_full();
+        db.names.pop_back();
+        db.names.back().first += std::move(args);
+      }
+      first = t1;
+    } else
+      first = t;
+  }
+  return first;
+}
+
+// <unresolved-type> ::= <template-param>
+//                   ::= <decltype>
+//                   ::= <substitution>
+
+template <class C>
+static const char *parse_unresolved_type(const char *first, const char *last,
+                                         C &db) {
+  if (first != last) {
+    const char *t = first;
+    switch (*first) {
+    case 'T': {
+      size_t k0 = db.names.size();
+      t = parse_template_param(first, last, db);
+      size_t k1 = db.names.size();
+      if (t != first && k1 == k0 + 1) {
+        db.subs.push_back(typename C::sub_type(1, db.names.back()));
+        first = t;
+      } else {
+        for (; k1 != k0; --k1)
+          db.names.pop_back();
+      }
+      break;
+    }
+    case 'D':
+      t = parse_decltype(first, last, db);
+      if (t != first) {
+        if (db.names.empty())
+          return first;
+        db.subs.push_back(typename C::sub_type(1, db.names.back()));
+        first = t;
+      }
+      break;
+    case 'S':
+      t = parse_substitution(first, last, db);
+      if (t != first)
+        first = t;
+      else {
+        if (last - first > 2 && first[1] == 't') {
+          t = parse_unqualified_name(first + 2, last, db);
+          if (t != first + 2) {
+            if (db.names.empty())
+              return first;
+            db.names.back().first.insert(0, "std::");
+            db.subs.push_back(typename C::sub_type(1, db.names.back()));
+            first = t;
+          }
+        }
+      }
+      break;
+    }
+  }
+  return first;
+}
+
+// <destructor-name> ::= <unresolved-type>                               # e.g.,
+// ~T or ~decltype(f())
+//                   ::= <simple-id>                                     # e.g.,
+//                   ~A<2*N>
+
+template <class C>
+static const char *parse_destructor_name(const char *first, const char *last,
+                                         C &db) {
+  if (first != last) {
+    const char *t = parse_unresolved_type(first, last, db);
+    if (t == first)
+      t = parse_simple_id(first, last, db);
+    if (t != first) {
+      if (db.names.empty())
+        return first;
+      db.names.back().first.insert(0, "~");
+      first = t;
+    }
+  }
+  return first;
+}
+
+// <base-unresolved-name> ::= <simple-id>                                #
+// unresolved name
+//          extension     ::= <operator-name>                            #
+//          unresolved operator-function-id
+//          extension     ::= <operator-name> <template-args>            #
+//          unresolved operator template-id
+//                        ::= on <operator-name>                         #
+//                        unresolved operator-function-id
+//                        ::= on <operator-name> <template-args>         #
+//                        unresolved operator template-id
+//                        ::= dn <destructor-name>                       #
+//                        destructor or pseudo-destructor;
+//                                                                         #
+//                                                                         e.g.
+//                                                                         ~X or
+//                                                                         ~X<N-1>
+
+template <class C>
+static const char *parse_base_unresolved_name(const char *first,
+                                              const char *last, C &db) {
+  if (last - first >= 2) {
+    if ((first[0] == 'o' || first[0] == 'd') && first[1] == 'n') {
+      if (first[0] == 'o') {
+        const char *t = parse_operator_name(first + 2, last, db);
+        if (t != first + 2) {
+          first = parse_template_args(t, last, db);
+          if (first != t) {
+            if (db.names.size() < 2)
+              return first;
+            auto args = db.names.back().move_full();
+            db.names.pop_back();
+            db.names.back().first += std::move(args);
+          }
+        }
+      } else {
+        const char *t = parse_destructor_name(first + 2, last, db);
+        if (t != first + 2)
+          first = t;
+      }
+    } else {
+      const char *t = parse_simple_id(first, last, db);
+      if (t == first) {
+        t = parse_operator_name(first, last, db);
+        if (t != first) {
+          first = parse_template_args(t, last, db);
+          if (first != t) {
+            if (db.names.size() < 2)
+              return first;
+            auto args = db.names.back().move_full();
+            db.names.pop_back();
+            db.names.back().first += std::move(args);
+          }
+        }
+      } else
+        first = t;
+    }
+  }
+  return first;
+}
+
+// <unresolved-qualifier-level> ::= <simple-id>
+
+template <class C>
+static const char *parse_unresolved_qualifier_level(const char *first,
+                                                    const char *last, C &db) {
+  return parse_simple_id(first, last, db);
+}
+
+// <unresolved-name>
+//  extension        ::= srN <unresolved-type> [<template-args>]
+//  <unresolved-qualifier-level>* E <base-unresolved-name>
+//                   ::= [gs] <base-unresolved-name>                     # x or
+//                   (with "gs") ::x
+//                   ::= [gs] sr <unresolved-qualifier-level>+ E
+//                   <base-unresolved-name>
+//                                                                       # A::x,
+//                                                                       N::y,
+//                                                                       A<T>::z;
+//                                                                       "gs"
+//                                                                       means
+//                                                                       leading
+//                                                                       "::"
+//                   ::= sr <unresolved-type> <base-unresolved-name>     # T::x
+//                   / decltype(p)::x
+//  extension        ::= sr <unresolved-type> <template-args>
+//  <base-unresolved-name>
+//                                                                       #
+//                                                                       T::N::x
+//                                                                       /decltype(p)::N::x
+//  (ignored)        ::= srN <unresolved-type>  <unresolved-qualifier-level>+ E
+//  <base-unresolved-name>
+
+template <class C>
+static const char *parse_unresolved_name(const char *first, const char *last,
+                                         C &db) {
+  if (last - first > 2) {
+    const char *t = first;
+    bool global = false;
+    if (t[0] == 'g' && t[1] == 's') {
+      global = true;
+      t += 2;
+    }
+    const char *t2 = parse_base_unresolved_name(t, last, db);
+    if (t2 != t) {
+      if (global) {
+        if (db.names.empty())
+          return first;
+        db.names.back().first.insert(0, "::");
+      }
+      first = t2;
+    } else if (last - t > 2 && t[0] == 's' && t[1] == 'r') {
+      if (t[2] == 'N') {
+        t += 3;
+        const char *t1 = parse_unresolved_type(t, last, db);
+        if (t1 == t || t1 == last)
+          return first;
+        t = t1;
+        t1 = parse_template_args(t, last, db);
+        if (t1 != t) {
+          if (db.names.size() < 2)
+            return first;
+          auto args = db.names.back().move_full();
+          db.names.pop_back();
+          db.names.back().first += std::move(args);
+          t = t1;
+          if (t == last) {
+            db.names.pop_back();
+            return first;
+          }
+        }
+        while (*t != 'E') {
+          t1 = parse_unresolved_qualifier_level(t, last, db);
+          if (t1 == t || t1 == last || db.names.size() < 2)
+            return first;
+          auto s = db.names.back().move_full();
+          db.names.pop_back();
+          db.names.back().first += "::" + std::move(s);
+          t = t1;
+        }
+        ++t;
+        t1 = parse_base_unresolved_name(t, last, db);
+        if (t1 == t) {
+          if (!db.names.empty())
+            db.names.pop_back();
+          return first;
+        }
+        if (db.names.size() < 2)
+          return first;
+        auto s = db.names.back().move_full();
+        db.names.pop_back();
+        db.names.back().first += "::" + std::move(s);
+        first = t1;
+      } else {
+        t += 2;
+        const char *t1 = parse_unresolved_type(t, last, db);
+        if (t1 != t) {
+          t = t1;
+          t1 = parse_template_args(t, last, db);
+          if (t1 != t) {
+            if (db.names.size() < 2)
+              return first;
+            auto args = db.names.back().move_full();
+            db.names.pop_back();
+            db.names.back().first += std::move(args);
+            t = t1;
+          }
+          t1 = parse_base_unresolved_name(t, last, db);
+          if (t1 == t) {
+            if (!db.names.empty())
+              db.names.pop_back();
+            return first;
+          }
+          if (db.names.size() < 2)
+            return first;
+          auto s = db.names.back().move_full();
+          db.names.pop_back();
+          db.names.back().first += "::" + std::move(s);
+          first = t1;
+        } else {
+          t1 = parse_unresolved_qualifier_level(t, last, db);
+          if (t1 == t || t1 == last)
+            return first;
+          t = t1;
+          if (global) {
+            if (db.names.empty())
+              return first;
+            db.names.back().first.insert(0, "::");
+          }
+          while (*t != 'E') {
+            t1 = parse_unresolved_qualifier_level(t, last, db);
+            if (t1 == t || t1 == last || db.names.size() < 2)
+              return first;
+            auto s = db.names.back().move_full();
+            db.names.pop_back();
+            db.names.back().first += "::" + std::move(s);
+            t = t1;
+          }
+          ++t;
+          t1 = parse_base_unresolved_name(t, last, db);
+          if (t1 == t) {
+            if (!db.names.empty())
+              db.names.pop_back();
+            return first;
+          }
+          if (db.names.size() < 2)
+            return first;
+          auto s = db.names.back().move_full();
+          db.names.pop_back();
+          db.names.back().first += "::" + std::move(s);
+          first = t1;
+        }
+      }
+    }
+  }
+  return first;
+}
+
+// dt <expression> <unresolved-name>                    # expr.name
+
+template <class C>
+static const char *parse_dot_expr(const char *first, const char *last, C &db) {
+  if (last - first >= 3 && first[0] == 'd' && first[1] == 't') {
+    const char *t = parse_expression(first + 2, last, db);
+    if (t != first + 2) {
+      const char *t1 = parse_unresolved_name(t, last, db);
+      if (t1 != t) {
+        if (db.names.size() < 2)
+          return first;
+        auto name = db.names.back().move_full();
+        db.names.pop_back();
+        if (db.names.empty())
+          return first;
+        db.names.back().first += "." + name;
+        first = t1;
+      }
+    }
+  }
+  return first;
+}
+
+// cl <expression>+ E                                   # call
+
+template <class C>
+static const char *parse_call_expr(const char *first, const char *last, C &db) {
+  if (last - first >= 4 && first[0] == 'c' && first[1] == 'l') {
+    const char *t = parse_expression(first + 2, last, db);
+    if (t != first + 2) {
+      if (t == last)
+        return first;
+      if (db.names.empty())
+        return first;
+      db.names.back().first += db.names.back().second;
+      db.names.back().second = std::string();
+      db.names.back().first.append("(");
+      bool first_expr = true;
+      while (*t != 'E') {
+        const char *t1 = parse_expression(t, last, db);
+        if (t1 == t || t1 == last)
+          return first;
+        if (db.names.empty())
+          return first;
+        auto tmp = db.names.back().move_full();
+        db.names.pop_back();
+        if (!tmp.empty()) {
+          if (db.names.empty())
+            return first;
+          if (!first_expr) {
+            db.names.back().first.append(", ");
+            first_expr = false;
+          }
+          db.names.back().first.append(tmp);
+        }
+        t = t1;
+      }
+      ++t;
+      if (db.names.empty())
+        return first;
+      db.names.back().first.append(")");
+      first = t;
+    }
+  }
+  return first;
+}
+
+// [gs] nw <expression>* _ <type> E                     # new (expr-list) type
+// [gs] nw <expression>* _ <type> <initializer>         # new (expr-list) type
+// (init)
+// [gs] na <expression>* _ <type> E                     # new[] (expr-list) type
+// [gs] na <expression>* _ <type> <initializer>         # new[] (expr-list) type
+// (init)
+// <initializer> ::= pi <expression>* E                 # parenthesized
+// initialization
+
+template <class C>
+static const char *parse_new_expr(const char *first, const char *last, C &db) {
+  if (last - first >= 4) {
+    const char *t = first;
+    bool parsed_gs = false;
+    if (t[0] == 'g' && t[1] == 's') {
+      t += 2;
+      parsed_gs = true;
+    }
+    if (t[0] == 'n' && (t[1] == 'w' || t[1] == 'a')) {
+      bool is_array = t[1] == 'a';
+      t += 2;
+      if (t == last)
+        return first;
+      bool has_expr_list = false;
+      bool first_expr = true;
+      while (*t != '_') {
+        const char *t1 = parse_expression(t, last, db);
+        if (t1 == t || t1 == last)
+          return first;
+        has_expr_list = true;
+        if (!first_expr) {
+          if (db.names.empty())
+            return first;
+          auto tmp = db.names.back().move_full();
+          db.names.pop_back();
+          if (!tmp.empty()) {
+            if (db.names.empty())
+              return first;
+            db.names.back().first.append(", ");
+            db.names.back().first.append(tmp);
+            first_expr = false;
+          }
+        }
+        t = t1;
+      }
+      ++t;
+      const char *t1 = parse_type(t, last, db);
+      if (t1 == t || t1 == last)
+        return first;
+      t = t1;
+      bool has_init = false;
+      if (last - t >= 3 && t[0] == 'p' && t[1] == 'i') {
+        t += 2;
+        has_init = true;
+        first_expr = true;
+        while (*t != 'E') {
+          t1 = parse_expression(t, last, db);
+          if (t1 == t || t1 == last)
+            return first;
+          if (!first_expr) {
+            if (db.names.empty())
+              return first;
+            auto tmp = db.names.back().move_full();
+            db.names.pop_back();
+            if (!tmp.empty()) {
+              if (db.names.empty())
+                return first;
+              db.names.back().first.append(", ");
+              db.names.back().first.append(tmp);
+              first_expr = false;
+            }
+          }
+          t = t1;
+        }
+      }
+      if (*t != 'E')
+        return first;
+      std::string init_list;
+      if (has_init) {
+        if (db.names.empty())
+          return first;
+        init_list = db.names.back().move_full();
+        db.names.pop_back();
+      }
+      if (db.names.empty())
+        return first;
+      auto type = db.names.back().move_full();
+      db.names.pop_back();
+      std::string expr_list;
+      if (has_expr_list) {
+        if (db.names.empty())
+          return first;
+        expr_list = db.names.back().move_full();
+        db.names.pop_back();
+      }
+      std::string r;
+      if (parsed_gs)
+        r = "::";
+      if (is_array)
+        r += "[] ";
+      else
+        r += " ";
+      if (has_expr_list)
+        r += "(" + expr_list + ") ";
+      r += type;
+      if (has_init)
+        r += " (" + init_list + ")";
+      db.names.push_back(std::move(r));
+      first = t + 1;
+    }
+  }
+  return first;
+}
+
+// cv <type> <expression>                               # conversion with one
+// argument
+// cv <type> _ <expression>* E                          # conversion with a
+// different number of arguments
+
+template <class C>
+static const char *parse_conversion_expr(const char *first, const char *last,
+                                         C &db) {
+  if (last - first >= 3 && first[0] == 'c' && first[1] == 'v') {
+    bool try_to_parse_template_args = db.try_to_parse_template_args;
+    db.try_to_parse_template_args = false;
+    const char *t = parse_type(first + 2, last, db);
+    db.try_to_parse_template_args = try_to_parse_template_args;
+    if (t != first + 2 && t != last) {
+      if (*t != '_') {
+        const char *t1 = parse_expression(t, last, db);
+        if (t1 == t)
+          return first;
+        t = t1;
+      } else {
+        ++t;
+        if (t == last)
+          return first;
+        if (*t == 'E')
+          db.names.emplace_back();
+        else {
+          bool first_expr = true;
+          while (*t != 'E') {
+            const char *t1 = parse_expression(t, last, db);
+            if (t1 == t || t1 == last)
+              return first;
+            if (!first_expr) {
+              if (db.names.empty())
+                return first;
+              auto tmp = db.names.back().move_full();
+              db.names.pop_back();
+              if (!tmp.empty()) {
+                if (db.names.empty())
+                  return first;
+                db.names.back().first.append(", ");
+                db.names.back().first.append(tmp);
+                first_expr = false;
+              }
+            }
+            t = t1;
+          }
+        }
+        ++t;
+      }
+      if (db.names.size() < 2)
+        return first;
+      auto tmp = db.names.back().move_full();
+      db.names.pop_back();
+      db.names.back() = "(" + db.names.back().move_full() + ")(" + tmp + ")";
+      first = t;
+    }
+  }
+  return first;
+}
+
+// pt <expression> <expression>                    # expr->name
+
+template <class C>
+static const char *parse_arrow_expr(const char *first, const char *last,
+                                    C &db) {
+  if (last - first >= 3 && first[0] == 'p' && first[1] == 't') {
+    const char *t = parse_expression(first + 2, last, db);
+    if (t != first + 2) {
+      const char *t1 = parse_expression(t, last, db);
+      if (t1 != t) {
+        if (db.names.size() < 2)
+          return first;
+        auto tmp = db.names.back().move_full();
+        db.names.pop_back();
+        db.names.back().first += "->";
+        db.names.back().first += tmp;
+        first = t1;
+      }
+    }
+  }
+  return first;
+}
+
+//  <ref-qualifier> ::= R                   # & ref-qualifier
+//  <ref-qualifier> ::= O                   # && ref-qualifier
+
+// <function-type> ::= F [Y] <bare-function-type> [<ref-qualifier>] E
+
+template <class C>
+static const char *parse_function_type(const char *first, const char *last,
+                                       C &db) {
+  if (first != last && *first == 'F') {
+    const char *t = first + 1;
+    if (t != last) {
+      if (*t == 'Y') {
+        /* extern "C" */
+        if (++t == last)
+          return first;
+      }
+      const char *t1 = parse_type(t, last, db);
+      if (t1 != t) {
+        t = t1;
+        std::string sig("(");
+        int ref_qual = 0;
+        while (true) {
+          if (t == last) {
+            db.names.pop_back();
+            return first;
+          }
+          if (*t == 'E') {
+            ++t;
+            break;
+          }
+          if (*t == 'v') {
+            ++t;
+            continue;
+          }
+          if (*t == 'R' && t + 1 != last && t[1] == 'E') {
+            ref_qual = 1;
+            ++t;
+            continue;
+          }
+          if (*t == 'O' && t + 1 != last && t[1] == 'E') {
+            ref_qual = 2;
+            ++t;
+            continue;
+          }
+          size_t k0 = db.names.size();
+          t1 = parse_type(t, last, db);
+          size_t k1 = db.names.size();
+          if (t1 == t || t1 == last)
+            return first;
+          for (size_t k = k0; k < k1; ++k) {
+            if (sig.size() > 1)
+              sig += ", ";
+            sig += db.names[k].move_full();
+          }
+          for (size_t k = k0; k < k1; ++k)
+            db.names.pop_back();
+          t = t1;
+        }
+        sig += ")";
+        switch (ref_qual) {
+        case 1:
+          sig += " &";
+          break;
+        case 2:
+          sig += " &&";
+          break;
+        }
+        if (db.names.empty())
+          return first;
+        db.names.back().first += " ";
+        db.names.back().second.insert(0, sig);
+        first = t;
+      }
+    }
+  }
+  return first;
+}
+
+// <pointer-to-member-type> ::= M <class type> <member type>
+
+template <class C>
+static const char *parse_pointer_to_member_type(const char *first,
+                                                const char *last, C &db) {
+  if (first != last && *first == 'M') {
+    const char *t = parse_type(first + 1, last, db);
+    if (t != first + 1) {
+      const char *t2 = parse_type(t, last, db);
+      if (t2 != t) {
+        if (db.names.size() < 2)
+          return first;
+        auto func = std::move(db.names.back());
+        db.names.pop_back();
+        auto class_type = std::move(db.names.back());
+        if (!func.second.empty() && func.second.front() == '(') {
+          db.names.back().first =
+              std::move(func.first) + "(" + class_type.move_full() + "::*";
+          db.names.back().second = ")" + std::move(func.second);
+        } else {
+          db.names.back().first =
+              std::move(func.first) + " " + class_type.move_full() + "::*";
+          db.names.back().second = std::move(func.second);
+        }
+        first = t2;
+      }
+    }
+  }
+  return first;
+}
+
+// <array-type> ::= A <positive dimension number> _ <element type>
+//              ::= A [<dimension expression>] _ <element type>
+
+template <class C>
+static const char *parse_array_type(const char *first, const char *last,
+                                    C &db) {
+  if (first != last && *first == 'A' && first + 1 != last) {
+    if (first[1] == '_') {
+      const char *t = parse_type(first + 2, last, db);
+      if (t != first + 2) {
+        if (db.names.empty())
+          return first;
+        if (db.names.back().second.substr(0, 2) == " [")
+          db.names.back().second.erase(0, 1);
+        db.names.back().second.insert(0, " []");
+        first = t;
+      }
+    } else if ('1' <= first[1] && first[1] <= '9') {
+      const char *t = parse_number(first + 1, last);
+      if (t != last && *t == '_') {
+        const char *t2 = parse_type(t + 1, last, db);
+        if (t2 != t + 1) {
+          if (db.names.empty())
+            return first;
+          if (db.names.back().second.substr(0, 2) == " [")
+            db.names.back().second.erase(0, 1);
+          db.names.back().second.insert(0,
+                                        " [" + std::string(first + 1, t) + "]");
+          first = t2;
+        }
+      }
+    } else {
+      const char *t = parse_expression(first + 1, last, db);
+      if (t != first + 1 && t != last && *t == '_') {
+        const char *t2 = parse_type(++t, last, db);
+        if (t2 != t) {
+          if (db.names.size() < 2)
+            return first;
+          auto type = std::move(db.names.back());
+          db.names.pop_back();
+          auto expr = std::move(db.names.back());
+          db.names.back().first = std::move(type.first);
+          if (type.second.substr(0, 2) == " [")
+            type.second.erase(0, 1);
+          db.names.back().second =
+              " [" + expr.move_full() + "]" + std::move(type.second);
+          first = t2;
+        }
+      }
+    }
+  }
+  return first;
+}
+
+// <decltype>  ::= Dt <expression> E  # decltype of an id-expression or class
+// member access (C++0x)
+//             ::= DT <expression> E  # decltype of an expression (C++0x)
+
+template <class C>
+static const char *parse_decltype(const char *first, const char *last, C &db) {
+  if (last - first >= 4 && first[0] == 'D') {
+    switch (first[1]) {
+    case 't':
+    case 'T': {
+      const char *t = parse_expression(first + 2, last, db);
+      if (t != first + 2 && t != last && *t == 'E') {
+        if (db.names.empty())
+          return first;
+        db.names.back() = "decltype(" + db.names.back().move_full() + ")";
+        first = t + 1;
+      }
+    } break;
+    }
+  }
+  return first;
+}
+
+// extension:
+// <vector-type>           ::= Dv <positive dimension number> _
+//                                    <extended element type>
+//                         ::= Dv [<dimension expression>] _ <element type>
+// <extended element type> ::= <element type>
+//                         ::= p # AltiVec vector pixel
+
+template <class C>
+static const char *parse_vector_type(const char *first, const char *last,
+                                     C &db) {
+  if (last - first > 3 && first[0] == 'D' && first[1] == 'v') {
+    if ('1' <= first[2] && first[2] <= '9') {
+      const char *t = parse_number(first + 2, last);
+      if (t == last || *t != '_')
+        return first;
+      const char *num = first + 2;
+      size_t sz = static_cast<size_t>(t - num);
+      if (++t != last) {
+        if (*t != 'p') {
+          const char *t1 = parse_type(t, last, db);
+          if (t1 != t) {
+            if (db.names.empty())
+              return first;
+            db.names.back().first += " vector[" + std::string(num, sz) + "]";
+            first = t1;
+          }
+        } else {
+          ++t;
+          db.names.push_back("pixel vector[" + std::string(num, sz) + "]");
+          first = t;
+        }
+      }
+    } else {
+      std::string num;
+      const char *t1 = first + 2;
+      if (*t1 != '_') {
+        const char *t = parse_expression(t1, last, db);
+        if (t != t1) {
+          if (db.names.empty())
+            return first;
+          num = db.names.back().move_full();
+          db.names.pop_back();
+          t1 = t;
+        }
+      }
+      if (t1 != last && *t1 == '_' && ++t1 != last) {
+        const char *t = parse_type(t1, last, db);
+        if (t != t1) {
+          if (db.names.empty())
+            return first;
+          db.names.back().first += " vector[" + num + "]";
+          first = t;
+        }
+      }
+    }
+  }
+  return first;
+}
+
+// <type> ::= <builtin-type>
+//        ::= <function-type>
+//        ::= <class-enum-type>
+//        ::= <array-type>
+//        ::= <pointer-to-member-type>
+//        ::= <template-param>
+//        ::= <template-template-param> <template-args>
+//        ::= <decltype>
+//        ::= <substitution>
+//        ::= <CV-qualifiers> <type>
+//        ::= P <type>        # pointer-to
+//        ::= R <type>        # reference-to
+//        ::= O <type>        # rvalue reference-to (C++0x)
+//        ::= C <type>        # complex pair (C 2000)
+//        ::= G <type>        # imaginary (C 2000)
+//        ::= Dp <type>       # pack expansion (C++0x)
+//        ::= U <source-name> <type>  # vendor extended type qualifier
+// extension := U <objc-name> <objc-type>  # objc-type<identifier>
+// extension := <vector-type> # <vector-type> starts with Dv
+
+// <objc-name> ::= <k0 number> objcproto <k1 number> <identifier>  # k0 = 9 +
+// <number of digits in k1> + k1
+// <objc-type> := <source-name>  # PU<11+>objcproto 11objc_object<source-name>
+// 11objc_object -> id<source-name>
+
+template <class C>
+static const char *parse_type(const char *first, const char *last, C &db) {
+  if (first != last) {
+    switch (*first) {
+    case 'r':
+    case 'V':
+    case 'K': {
+      unsigned cv = 0;
+      const char *t = parse_cv_qualifiers(first, last, cv);
+      if (t != first) {
+        bool is_function = *t == 'F';
+        size_t k0 = db.names.size();
+        const char *t1 = parse_type(t, last, db);
+        size_t k1 = db.names.size();
+        if (t1 != t) {
+          if (is_function)
+            db.subs.pop_back();
+          db.subs.emplace_back();
+          for (size_t k = k0; k < k1; ++k) {
+            if (is_function) {
+              size_t p = db.names[k].second.size();
+              if (db.names[k].second[p - 2] == '&')
+                p -= 3;
+              else if (db.names[k].second.back() == '&')
+                p -= 2;
+              if (cv & 1) {
+                db.names[k].second.insert(p, " const");
+                p += 6;
+              }
+              if (cv & 2) {
+                db.names[k].second.insert(p, " volatile");
+                p += 9;
+              }
+              if (cv & 4)
+                db.names[k].second.insert(p, " restrict");
+            } else {
+              if (cv & 1)
+                db.names[k].first.append(" const");
+              if (cv & 2)
+                db.names[k].first.append(" volatile");
+              if (cv & 4)
+                db.names[k].first.append(" restrict");
+            }
+            db.subs.back().push_back(db.names[k]);
+          }
+          first = t1;
+        }
+      }
+    } break;
+    default: {
+      const char *t = parse_builtin_type(first, last, db);
+      if (t != first) {
+        first = t;
+      } else {
+        switch (*first) {
+        case 'A':
+          t = parse_array_type(first, last, db);
+          if (t != first) {
+            if (db.names.empty())
+              return first;
+            first = t;
+            db.subs.push_back(typename C::sub_type(1, db.names.back()));
+          }
+          break;
+        case 'C':
+          t = parse_type(first + 1, last, db);
+          if (t != first + 1) {
+            if (db.names.empty())
+              return first;
+            db.names.back().first.append(" complex");
+            first = t;
+            db.subs.push_back(typename C::sub_type(1, db.names.back()));
+          }
+          break;
+        case 'F':
+          t = parse_function_type(first, last, db);
+          if (t != first) {
+            if (db.names.empty())
+              return first;
+            first = t;
+            db.subs.push_back(typename C::sub_type(1, db.names.back()));
+          }
+          break;
+        case 'G':
+          t = parse_type(first + 1, last, db);
+          if (t != first + 1) {
+            if (db.names.empty())
+              return first;
+            db.names.back().first.append(" imaginary");
+            first = t;
+            db.subs.push_back(typename C::sub_type(1, db.names.back()));
+          }
+          break;
+        case 'M':
+          t = parse_pointer_to_member_type(first, last, db);
+          if (t != first) {
+            if (db.names.empty())
+              return first;
+            first = t;
+            db.subs.push_back(typename C::sub_type(1, db.names.back()));
+          }
+          break;
+        case 'O': {
+          size_t k0 = db.names.size();
+          t = parse_type(first + 1, last, db);
+          size_t k1 = db.names.size();
+          if (t != first + 1) {
+            db.subs.emplace_back();
+            for (size_t k = k0; k < k1; ++k) {
+              if (db.names[k].second.substr(0, 2) == " [") {
+                db.names[k].first += " (";
+                db.names[k].second.insert(0, ")");
+              } else if (!db.names[k].second.empty() &&
+                         db.names[k].second.front() == '(') {
+                db.names[k].first += "(";
+                db.names[k].second.insert(0, ")");
+              }
+              db.names[k].first.append("&&");
+              db.subs.back().push_back(db.names[k]);
+            }
+            first = t;
+          }
+          break;
+        }
+        case 'P': {
+          size_t k0 = db.names.size();
+          t = parse_type(first + 1, last, db);
+          size_t k1 = db.names.size();
+          if (t != first + 1) {
+            db.subs.emplace_back();
+            for (size_t k = k0; k < k1; ++k) {
+              if (db.names[k].second.substr(0, 2) == " [") {
+                db.names[k].first += " (";
+                db.names[k].second.insert(0, ")");
+              } else if (!db.names[k].second.empty() &&
+                         db.names[k].second.front() == '(') {
+                db.names[k].first += "(";
+                db.names[k].second.insert(0, ")");
+              }
+              if (first[1] != 'U' ||
+                  db.names[k].first.substr(0, 12) != "objc_object<") {
+                db.names[k].first.append("*");
+              } else {
+                db.names[k].first.replace(0, 11, "id");
+              }
+              db.subs.back().push_back(db.names[k]);
+            }
+            first = t;
+          }
+          break;
+        }
+        case 'R': {
+          size_t k0 = db.names.size();
+          t = parse_type(first + 1, last, db);
+          size_t k1 = db.names.size();
+          if (t != first + 1) {
+            db.subs.emplace_back();
+            for (size_t k = k0; k < k1; ++k) {
+              if (db.names[k].second.substr(0, 2) == " [") {
+                db.names[k].first += " (";
+                db.names[k].second.insert(0, ")");
+              } else if (!db.names[k].second.empty() &&
+                         db.names[k].second.front() == '(') {
+                db.names[k].first += "(";
+                db.names[k].second.insert(0, ")");
+              }
+              db.names[k].first.append("&");
+              db.subs.back().push_back(db.names[k]);
+            }
+            first = t;
+          }
+          break;
+        }
+        case 'T': {
+          size_t k0 = db.names.size();
+          t = parse_template_param(first, last, db);
+          size_t k1 = db.names.size();
+          if (t != first) {
+            db.subs.emplace_back();
+            for (size_t k = k0; k < k1; ++k)
+              db.subs.back().push_back(db.names[k]);
+            if (db.try_to_parse_template_args && k1 == k0 + 1) {
+              const char *t1 = parse_template_args(t, last, db);
+              if (t1 != t) {
+                auto args = db.names.back().move_full();
+                db.names.pop_back();
+                db.names.back().first += std::move(args);
+                db.subs.push_back(typename C::sub_type(1, db.names.back()));
+                t = t1;
+              }
+            }
+            first = t;
+          }
+          break;
+        }
+        case 'U':
+          if (first + 1 != last) {
+            t = parse_source_name(first + 1, last, db);
+            if (t != first + 1) {
+              const char *t2 = parse_type(t, last, db);
+              if (t2 != t) {
+                if (db.names.size() < 2)
+                  return first;
+                auto type = db.names.back().move_full();
+                db.names.pop_back();
+                if (db.names.back().first.substr(0, 9) != "objcproto") {
+                  db.names.back() = type + " " + db.names.back().move_full();
+                } else {
+                  auto proto = db.names.back().move_full();
+                  db.names.pop_back();
+                  t = parse_source_name(proto.data() + 9,
+                                        proto.data() + proto.size(), db);
+                  if (t != proto.data() + 9) {
+                    db.names.back() =
+                        type + "<" + db.names.back().move_full() + ">";
+                  } else {
+                    db.names.push_back(type + " " + proto);
+                  }
+                }
+                db.subs.push_back(typename C::sub_type(1, db.names.back()));
+                first = t2;
+              }
+            }
+          }
+          break;
+        case 'S':
+          if (first + 1 != last && first[1] == 't') {
+            t = parse_name(first, last, db);
+            if (t != first) {
+              if (db.names.empty())
+                return first;
+              db.subs.push_back(typename C::sub_type(1, db.names.back()));
+              first = t;
+            }
+          } else {
+            t = parse_substitution(first, last, db);
+            if (t != first) {
+              first = t;
+              // Parsed a substitution.  If the substitution is a
+              //  <template-param> it might be followed by <template-args>.
+              t = parse_template_args(first, last, db);
+              if (t != first) {
+                if (db.names.size() < 2)
+                  return first;
+                auto template_args = db.names.back().move_full();
+                db.names.pop_back();
+                db.names.back().first += template_args;
+                // Need to create substitution for <template-template-param>
+                // <template-args>
+                db.subs.push_back(typename C::sub_type(1, db.names.back()));
+                first = t;
+              }
+            }
+          }
+          break;
+        case 'D':
+          if (first + 1 != last) {
+            switch (first[1]) {
+            case 'p': {
+              size_t k0 = db.names.size();
+              t = parse_type(first + 2, last, db);
+              size_t k1 = db.names.size();
+              if (t != first + 2) {
+                db.subs.emplace_back();
+                for (size_t k = k0; k < k1; ++k)
+                  db.subs.back().push_back(db.names[k]);
+                first = t;
+                return first;
+              }
+              break;
+            }
+            case 't':
+            case 'T':
+              t = parse_decltype(first, last, db);
+              if (t != first) {
+                if (db.names.empty())
+                  return first;
+                db.subs.push_back(typename C::sub_type(1, db.names.back()));
+                first = t;
+                return first;
+              }
+              break;
+            case 'v':
+              t = parse_vector_type(first, last, db);
+              if (t != first) {
+                if (db.names.empty())
+                  return first;
+                db.subs.push_back(typename C::sub_type(1, db.names.back()));
+                first = t;
+                return first;
+              }
+              break;
+            }
+          }
+        // drop through
+        default:
+          // must check for builtin-types before class-enum-types to avoid
+          // ambiguities with operator-names
+          t = parse_builtin_type(first, last, db);
+          if (t != first) {
+            first = t;
+          } else {
+            t = parse_name(first, last, db);
+            if (t != first) {
+              if (db.names.empty())
+                return first;
+              db.subs.push_back(typename C::sub_type(1, db.names.back()));
+              first = t;
+            }
+          }
+          break;
+        }
+      }
+      break;
+    }
+    }
+  }
+  return first;
+}
+
+//   <operator-name>
+//                   ::= aa    # &&
+//                   ::= ad    # & (unary)
+//                   ::= an    # &
+//                   ::= aN    # &=
+//                   ::= aS    # =
+//                   ::= cl    # ()
+//                   ::= cm    # ,
+//                   ::= co    # ~
+//                   ::= cv <type>    # (cast)
+//                   ::= da    # delete[]
+//                   ::= de    # * (unary)
+//                   ::= dl    # delete
+//                   ::= dv    # /
+//                   ::= dV    # /=
+//                   ::= eo    # ^
+//                   ::= eO    # ^=
+//                   ::= eq    # ==
+//                   ::= ge    # >=
+//                   ::= gt    # >
+//                   ::= ix    # []
+//                   ::= le    # <=
+//                   ::= li <source-name>  # operator ""
+//                   ::= ls    # <<
+//                   ::= lS    # <<=
+//                   ::= lt    # <
+//                   ::= mi    # -
+//                   ::= mI    # -=
+//                   ::= ml    # *
+//                   ::= mL    # *=
+//                   ::= mm    # -- (postfix in <expression> context)
+//                   ::= na    # new[]
+//                   ::= ne    # !=
+//                   ::= ng    # - (unary)
+//                   ::= nt    # !
+//                   ::= nw    # new
+//                   ::= oo    # ||
+//                   ::= or    # |
+//                   ::= oR    # |=
+//                   ::= pm    # ->*
+//                   ::= pl    # +
+//                   ::= pL    # +=
+//                   ::= pp    # ++ (postfix in <expression> context)
+//                   ::= ps    # + (unary)
+//                   ::= pt    # ->
+//                   ::= qu    # ?
+//                   ::= rm    # %
+//                   ::= rM    # %=
+//                   ::= rs    # >>
+//                   ::= rS    # >>=
+//                   ::= v <digit> <source-name>        # vendor extended
+//                   operator
+
+template <class C>
+static const char *parse_operator_name(const char *first, const char *last,
+                                       C &db) {
+  if (last - first >= 2) {
+    switch (first[0]) {
+    case 'a':
+      switch (first[1]) {
+      case 'a':
+        db.names.push_back("operator&&");
+        first += 2;
+        break;
+      case 'd':
+      case 'n':
+        db.names.push_back("operator&");
+        first += 2;
+        break;
+      case 'N':
+        db.names.push_back("operator&=");
+        first += 2;
+        break;
+      case 'S':
+        db.names.push_back("operator=");
+        first += 2;
+        break;
+      }
+      break;
+    case 'c':
+      switch (first[1]) {
+      case 'l':
+        db.names.push_back("operator()");
+        first += 2;
+        break;
+      case 'm':
+        db.names.push_back("operator,");
+        first += 2;
+        break;
+      case 'o':
+        db.names.push_back("operator~");
+        first += 2;
+        break;
+      case 'v': {
+        bool try_to_parse_template_args = db.try_to_parse_template_args;
+        db.try_to_parse_template_args = false;
+        const char *t = parse_type(first + 2, last, db);
+        db.try_to_parse_template_args = try_to_parse_template_args;
+        if (t != first + 2) {
+          if (db.names.empty())
+            return first;
+          db.names.back().first.insert(0, "operator ");
+          db.parsed_ctor_dtor_cv = true;
+          first = t;
+        }
+      } break;
+      }
+      break;
+    case 'd':
+      switch (first[1]) {
+      case 'a':
+        db.names.push_back("operator delete[]");
+        first += 2;
+        break;
+      case 'e':
+        db.names.push_back("operator*");
+        first += 2;
+        break;
+      case 'l':
+        db.names.push_back("operator delete");
+        first += 2;
+        break;
+      case 'v':
+        db.names.push_back("operator/");
+        first += 2;
+        break;
+      case 'V':
+        db.names.push_back("operator/=");
+        first += 2;
+        break;
+      }
+      break;
+    case 'e':
+      switch (first[1]) {
+      case 'o':
+        db.names.push_back("operator^");
+        first += 2;
+        break;
+      case 'O':
+        db.names.push_back("operator^=");
+        first += 2;
+        break;
+      case 'q':
+        db.names.push_back("operator==");
+        first += 2;
+        break;
+      }
+      break;
+    case 'g':
+      switch (first[1]) {
+      case 'e':
+        db.names.push_back("operator>=");
+        first += 2;
+        break;
+      case 't':
+        db.names.push_back("operator>");
+        first += 2;
+        break;
+      }
+      break;
+    case 'i':
+      if (first[1] == 'x') {
+        db.names.push_back("operator[]");
+        first += 2;
+      }
+      break;
+    case 'l':
+      switch (first[1]) {
+      case 'e':
+        db.names.push_back("operator<=");
+        first += 2;
+        break;
+      case 'i': {
+        const char *t = parse_source_name(first + 2, last, db);
+        if (t != first + 2) {
+          if (db.names.empty())
+            return first;
+          db.names.back().first.insert(0, "operator\"\" ");
+          first = t;
+        }
+      } break;
+      case 's':
+        db.names.push_back("operator<<");
+        first += 2;
+        break;
+      case 'S':
+        db.names.push_back("operator<<=");
+        first += 2;
+        break;
+      case 't':
+        db.names.push_back("operator<");
+        first += 2;
+        break;
+      }
+      break;
+    case 'm':
+      switch (first[1]) {
+      case 'i':
+        db.names.push_back("operator-");
+        first += 2;
+        break;
+      case 'I':
+        db.names.push_back("operator-=");
+        first += 2;
+        break;
+      case 'l':
+        db.names.push_back("operator*");
+        first += 2;
+        break;
+      case 'L':
+        db.names.push_back("operator*=");
+        first += 2;
+        break;
+      case 'm':
+        db.names.push_back("operator--");
+        first += 2;
+        break;
+      }
+      break;
+    case 'n':
+      switch (first[1]) {
+      case 'a':
+        db.names.push_back("operator new[]");
+        first += 2;
+        break;
+      case 'e':
+        db.names.push_back("operator!=");
+        first += 2;
+        break;
+      case 'g':
+        db.names.push_back("operator-");
+        first += 2;
+        break;
+      case 't':
+        db.names.push_back("operator!");
+        first += 2;
+        break;
+      case 'w':
+        db.names.push_back("operator new");
+        first += 2;
+        break;
+      }
+      break;
+    case 'o':
+      switch (first[1]) {
+      case 'o':
+        db.names.push_back("operator||");
+        first += 2;
+        break;
+      case 'r':
+        db.names.push_back("operator|");
+        first += 2;
+        break;
+      case 'R':
+        db.names.push_back("operator|=");
+        first += 2;
+        break;
+      }
+      break;
+    case 'p':
+      switch (first[1]) {
+      case 'm':
+        db.names.push_back("operator->*");
+        first += 2;
+        break;
+      case 'l':
+        db.names.push_back("operator+");
+        first += 2;
+        break;
+      case 'L':
+        db.names.push_back("operator+=");
+        first += 2;
+        break;
+      case 'p':
+        db.names.push_back("operator++");
+        first += 2;
+        break;
+      case 's':
+        db.names.push_back("operator+");
+        first += 2;
+        break;
+      case 't':
+        db.names.push_back("operator->");
+        first += 2;
+        break;
+      }
+      break;
+    case 'q':
+      if (first[1] == 'u') {
+        db.names.push_back("operator?");
+        first += 2;
+      }
+      break;
+    case 'r':
+      switch (first[1]) {
+      case 'm':
+        db.names.push_back("operator%");
+        first += 2;
+        break;
+      case 'M':
+        db.names.push_back("operator%=");
+        first += 2;
+        break;
+      case 's':
+        db.names.push_back("operator>>");
+        first += 2;
+        break;
+      case 'S':
+        db.names.push_back("operator>>=");
+        first += 2;
+        break;
+      }
+      break;
+    case 'v':
+      if (std::isdigit(first[1])) {
+        const char *t = parse_source_name(first + 2, last, db);
+        if (t != first + 2) {
+          if (db.names.empty())
+            return first;
+          db.names.back().first.insert(0, "operator ");
+          first = t;
+        }
+      }
+      break;
+    }
+  }
+  return first;
+}
+
+template <class C>
+static const char *parse_integer_literal(const char *first, const char *last,
+                                         const std::string &lit, C &db) {
+  const char *t = parse_number(first, last);
+  if (t != first && t != last && *t == 'E') {
+    if (lit.size() > 3)
+      db.names.push_back("(" + lit + ")");
+    else
+      db.names.emplace_back();
+    if (*first == 'n') {
+      db.names.back().first += '-';
+      ++first;
+    }
+    db.names.back().first.append(first, t);
+    if (lit.size() <= 3)
+      db.names.back().first += lit;
+    first = t + 1;
+  }
+  return first;
+}
+
+// <expr-primary> ::= L <type> <value number> E                          #
+// integer literal
+//                ::= L <type> <value float> E                           #
+//                floating literal
+//                ::= L <string type> E                                  #
+//                string literal
+//                ::= L <nullptr type> E                                 #
+//                nullptr literal (i.e., "LDnE")
+//                ::= L <type> <real-part float> _ <imag-part float> E   #
+//                complex floating point literal (C 2000)
+//                ::= L <mangled-name> E                                 #
+//                external name
+
+template <class C>
+static const char *parse_expr_primary(const char *first, const char *last,
+                                      C &db) {
+  if (last - first >= 4 && *first == 'L') {
+    switch (first[1]) {
+    case 'w': {
+      const char *t = parse_integer_literal(first + 2, last, "wchar_t", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'b':
+      if (first[3] == 'E') {
+        switch (first[2]) {
+        case '0':
+          db.names.push_back("false");
+          first += 4;
+          break;
+        case '1':
+          db.names.push_back("true");
+          first += 4;
+          break;
+        }
+      }
+      break;
+    case 'c': {
+      const char *t = parse_integer_literal(first + 2, last, "char", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'a': {
+      const char *t = parse_integer_literal(first + 2, last, "signed char", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'h': {
+      const char *t =
+          parse_integer_literal(first + 2, last, "unsigned char", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 's': {
+      const char *t = parse_integer_literal(first + 2, last, "short", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 't': {
+      const char *t =
+          parse_integer_literal(first + 2, last, "unsigned short", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'i': {
+      const char *t = parse_integer_literal(first + 2, last, "", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'j': {
+      const char *t = parse_integer_literal(first + 2, last, "u", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'l': {
+      const char *t = parse_integer_literal(first + 2, last, "l", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'm': {
+      const char *t = parse_integer_literal(first + 2, last, "ul", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'x': {
+      const char *t = parse_integer_literal(first + 2, last, "ll", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'y': {
+      const char *t = parse_integer_literal(first + 2, last, "ull", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'n': {
+      const char *t = parse_integer_literal(first + 2, last, "__int128", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'o': {
+      const char *t =
+          parse_integer_literal(first + 2, last, "unsigned __int128", db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'f': {
+      const char *t = parse_floating_number<float>(first + 2, last, db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'd': {
+      const char *t = parse_floating_number<double>(first + 2, last, db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case 'e': {
+      const char *t = parse_floating_number<long double>(first + 2, last, db);
+      if (t != first + 2)
+        first = t;
+    } break;
+    case '_':
+      if (first[2] == 'Z') {
+        const char *t = parse_encoding(first + 3, last, db);
+        if (t != first + 3 && t != last && *t == 'E')
+          first = t + 1;
+      }
+      break;
+    case 'T':
+      // Invalid mangled name per
+      //   http://sourcerytools.com/pipermail/cxx-abi-dev/2011-August/002422.html
+      break;
+    default: {
+      // might be named type
+      const char *t = parse_type(first + 1, last, db);
+      if (t != first + 1 && t != last) {
+        if (*t != 'E') {
+          const char *n = t;
+          for (; n != last && isdigit(*n); ++n)
+            ;
+          if (n != t && n != last && *n == 'E') {
+            if (db.names.empty())
+              return first;
+            db.names.back() =
+                "(" + db.names.back().move_full() + ")" + std::string(t, n);
+            first = n + 1;
+            break;
+          }
+        } else {
+          first = t + 1;
+          break;
+        }
+      }
+    }
+    }
+  }
+  return first;
+}
+
+static std::string base_name(std::string &s) {
+  if (s.empty())
+    return s;
+  if (s == "std::string") {
+    s = "std::basic_string<char, std::char_traits<char>, std::allocator<char> "
+        ">";
+    return "basic_string";
+  }
+  if (s == "std::istream") {
+    s = "std::basic_istream<char, std::char_traits<char> >";
+    return "basic_istream";
+  }
+  if (s == "std::ostream") {
+    s = "std::basic_ostream<char, std::char_traits<char> >";
+    return "basic_ostream";
+  }
+  if (s == "std::iostream") {
+    s = "std::basic_iostream<char, std::char_traits<char> >";
+    return "basic_iostream";
+  }
+  const char *const pf = s.data();
+  const char *pe = pf + s.size();
+  if (pe[-1] == '>') {
+    unsigned c = 1;
+    while (true) {
+      if (--pe == pf)
+        return std::string();
+      if (pe[-1] == '<') {
+        if (--c == 0) {
+          --pe;
+          break;
+        }
+      } else if (pe[-1] == '>')
+        ++c;
+    }
+  }
+  if (pe - pf <= 1)
+    return std::string();
+  const char *p0 = pe - 1;
+  for (; p0 != pf; --p0) {
+    if (*p0 == ':') {
+      ++p0;
+      break;
+    }
+  }
+  return std::string(p0, pe);
+}
+
+// <ctor-dtor-name> ::= C1    # complete object constructor
+//                  ::= C2    # base object constructor
+//                  ::= C3    # complete object allocating constructor
+//   extension      ::= C5    # ?
+//                  ::= D0    # deleting destructor
+//                  ::= D1    # complete object destructor
+//                  ::= D2    # base object destructor
+//   extension      ::= D5    # ?
+
+template <class C>
+static const char *parse_ctor_dtor_name(const char *first, const char *last,
+                                        C &db) {
+  if (last - first >= 2 && !db.names.empty()) {
+    switch (first[0]) {
+    case 'C':
+      switch (first[1]) {
+      case '1':
+      case '2':
+      case '3':
+      case '5':
+        if (db.names.empty())
+          return first;
+        db.names.push_back(base_name(db.names.back().first));
+        first += 2;
+        db.parsed_ctor_dtor_cv = true;
+        break;
+      }
+      break;
+    case 'D':
+      switch (first[1]) {
+      case '0':
+      case '1':
+      case '2':
+      case '5':
+        if (db.names.empty())
+          return first;
+        db.names.push_back("~" + base_name(db.names.back().first));
+        first += 2;
+        db.parsed_ctor_dtor_cv = true;
+        break;
+      }
+      break;
+    }
+  }
+  return first;
+}
+
+// <unnamed-type-name> ::= Ut [ <nonnegative number> ] _
+//                     ::= <closure-type-name>
+//
+// <closure-type-name> ::= Ul <lambda-sig> E [ <nonnegative number> ] _
+//
+// <lambda-sig> ::= <parameter type>+  # Parameter types or "v" if the lambda
+// has no parameters
+
+template <class C>
+static const char *parse_unnamed_type_name(const char *first, const char *last,
+                                           C &db) {
+  if (last - first > 2 && first[0] == 'U') {
+    char type = first[1];
+    switch (type) {
+    case 't': {
+      db.names.push_back(std::string("'unnamed"));
+      const char *t0 = first + 2;
+      if (t0 == last) {
+        db.names.pop_back();
+        return first;
+      }
+      if (std::isdigit(*t0)) {
+        const char *t1 = t0 + 1;
+        while (t1 != last && std::isdigit(*t1))
+          ++t1;
+        db.names.back().first.append(t0, t1);
+        t0 = t1;
+      }
+      db.names.back().first.push_back('\'');
+      if (t0 == last || *t0 != '_') {
+        db.names.pop_back();
+        return first;
+      }
+      first = t0 + 1;
+    } break;
+    case 'l': {
+      db.names.push_back(std::string("'lambda'("));
+      const char *t0 = first + 2;
+      if (first[2] == 'v') {
+        db.names.back().first += ')';
+        ++t0;
+      } else {
+        const char *t1 = parse_type(t0, last, db);
+        if (t1 == t0) {
+          if (!db.names.empty())
+            db.names.pop_back();
+          return first;
+        }
+        if (db.names.size() < 2)
+          return first;
+        auto tmp = db.names.back().move_full();
+        db.names.pop_back();
+        db.names.back().first.append(tmp);
+        t0 = t1;
+        while (true) {
+          t1 = parse_type(t0, last, db);
+          if (t1 == t0)
+            break;
+          if (db.names.size() < 2)
+            return first;
+          tmp = db.names.back().move_full();
+          db.names.pop_back();
+          if (!tmp.empty()) {
+            db.names.back().first.append(", ");
+            db.names.back().first.append(tmp);
+          }
+          t0 = t1;
+        }
+        if (db.names.empty())
+          return first;
+        db.names.back().first.append(")");
+      }
+      if (t0 == last || *t0 != 'E') {
+        if (!db.names.empty())
+          db.names.pop_back();
+        return first;
+      }
+      ++t0;
+      if (t0 == last) {
+        if (!db.names.empty())
+          db.names.pop_back();
+        return first;
+      }
+      if (std::isdigit(*t0)) {
+        const char *t1 = t0 + 1;
+        while (t1 != last && std::isdigit(*t1))
+          ++t1;
+        db.names.back().first.insert(db.names.back().first.begin() + 7, t0, t1);
+        t0 = t1;
+      }
+      if (t0 == last || *t0 != '_') {
+        if (!db.names.empty())
+          db.names.pop_back();
+        return first;
+      }
+      first = t0 + 1;
+    } break;
+    }
+  }
+  return first;
+}
+
+// <unqualified-name> ::= <operator-name>
+//                    ::= <ctor-dtor-name>
+//                    ::= <source-name>
+//                    ::= <unnamed-type-name>
+
+template <class C>
+static const char *parse_unqualified_name(const char *first, const char *last,
+                                          C &db) {
+  if (first != last) {
+    const char *t;
+    switch (*first) {
+    case 'C':
+    case 'D':
+      t = parse_ctor_dtor_name(first, last, db);
+      if (t != first)
+        first = t;
+      break;
+    case 'U':
+      t = parse_unnamed_type_name(first, last, db);
+      if (t != first)
+        first = t;
+      break;
+    case '1':
+    case '2':
+    case '3':
+    case '4':
+    case '5':
+    case '6':
+    case '7':
+    case '8':
+    case '9':
+      t = parse_source_name(first, last, db);
+      if (t != first)
+        first = t;
+      break;
+    default:
+      t = parse_operator_name(first, last, db);
+      if (t != first)
+        first = t;
+      break;
+    };
+  }
+  return first;
+}
+
+// <unscoped-name> ::= <unqualified-name>
+//                 ::= St <unqualified-name>   # ::std::
+// extension       ::= StL<unqualified-name>
+
+template <class C>
+static const char *parse_unscoped_name(const char *first, const char *last,
+                                       C &db) {
+  if (last - first >= 2) {
+    const char *t0 = first;
+    bool St = false;
+    if (first[0] == 'S' && first[1] == 't') {
+      t0 += 2;
+      St = true;
+      if (t0 != last && *t0 == 'L')
+        ++t0;
+    }
+    const char *t1 = parse_unqualified_name(t0, last, db);
+    if (t1 != t0) {
+      if (St) {
+        if (db.names.empty())
+          return first;
+        db.names.back().first.insert(0, "std::");
+      }
+      first = t1;
+    }
+  }
+  return first;
+}
+
+// at <type>                                            # alignof (a type)
+
+template <class C>
+static const char *parse_alignof_type(const char *first, const char *last,
+                                      C &db) {
+  if (last - first >= 3 && first[0] == 'a' && first[1] == 't') {
+    const char *t = parse_type(first + 2, last, db);
+    if (t != first + 2) {
+      if (db.names.empty())
+        return first;
+      db.names.back().first = "alignof (" + db.names.back().move_full() + ")";
+      first = t;
+    }
+  }
+  return first;
+}
+
+// az <expression>                                            # alignof (a
+// expression)
+
+template <class C>
+static const char *parse_alignof_expr(const char *first, const char *last,
+                                      C &db) {
+  if (last - first >= 3 && first[0] == 'a' && first[1] == 'z') {
+    const char *t = parse_expression(first + 2, last, db);
+    if (t != first + 2) {
+      if (db.names.empty())
+        return first;
+      db.names.back().first = "alignof (" + db.names.back().move_full() + ")";
+      first = t;
+    }
+  }
+  return first;
+}
+
+template <class C>
+static const char *parse_noexcept_expression(const char *first,
+                                             const char *last, C &db) {
+  const char *t1 = parse_expression(first, last, db);
+  if (t1 != first) {
+    if (db.names.empty())
+      return first;
+    db.names.back().first = "noexcept (" + db.names.back().move_full() + ")";
+    first = t1;
+  }
+  return first;
+}
+
+template <class C>
+static const char *parse_prefix_expression(const char *first, const char *last,
+                                           const std::string &op,
+                                           C &db) {
+  const char *t1 = parse_expression(first, last, db);
+  if (t1 != first) {
+    if (db.names.empty())
+      return first;
+    db.names.back().first = op + "(" + db.names.back().move_full() + ")";
+    first = t1;
+  }
+  return first;
+}
+
+template <class C>
+static const char *parse_binary_expression(const char *first, const char *last,
+                                           const std::string &op,
+                                           C &db) {
+  const char *t1 = parse_expression(first, last, db);
+  if (t1 != first) {
+    const char *t2 = parse_expression(t1, last, db);
+    if (t2 != t1) {
+      if (db.names.size() < 2)
+        return first;
+      auto op2 = db.names.back().move_full();
+      db.names.pop_back();
+      auto op1 = db.names.back().move_full();
+      auto &nm = db.names.back().first;
+      nm.clear();
+      if (op == ">")
+        nm += '(';
+      nm += "(" + op1 + ") " + op + " (" + op2 + ")";
+      if (op == ">")
+        nm += ')';
+      first = t2;
+    } else if (!db.names.empty())
+      db.names.pop_back();
+  }
+  return first;
+}
+
+// <expression> ::= <unary operator-name> <expression>
+//              ::= <binary operator-name> <expression> <expression>
+//              ::= <ternary operator-name> <expression> <expression>
+//              <expression>
+//              ::= cl <expression>+ E                                   # call
+//              ::= cv <type> <expression>                               #
+//              conversion with one argument
+//              ::= cv <type> _ <expression>* E                          #
+//              conversion with a different number of arguments
+//              ::= [gs] nw <expression>* _ <type> E                     # new
+//              (expr-list) type
+//              ::= [gs] nw <expression>* _ <type> <initializer>         # new
+//              (expr-list) type (init)
+//              ::= [gs] na <expression>* _ <type> E                     # new[]
+//              (expr-list) type
+//              ::= [gs] na <expression>* _ <type> <initializer>         # new[]
+//              (expr-list) type (init)
+//              ::= [gs] dl <expression>                                 #
+//              delete expression
+//              ::= [gs] da <expression>                                 #
+//              delete[] expression
+//              ::= pp_ <expression>                                     #
+//              prefix ++
+//              ::= mm_ <expression>                                     #
+//              prefix --
+//              ::= ti <type>                                            #
+//              typeid (type)
+//              ::= te <expression>                                      #
+//              typeid (expression)
+//              ::= dc <type> <expression>                               #
+//              dynamic_cast<type> (expression)
+//              ::= sc <type> <expression>                               #
+//              static_cast<type> (expression)
+//              ::= cc <type> <expression>                               #
+//              const_cast<type> (expression)
+//              ::= rc <type> <expression>                               #
+//              reinterpret_cast<type> (expression)
+//              ::= st <type>                                            #
+//              sizeof (a type)
+//              ::= sz <expression>                                      #
+//              sizeof (an expression)
+//              ::= at <type>                                            #
+//              alignof (a type)
+//              ::= az <expression>                                      #
+//              alignof (an expression)
+//              ::= nx <expression>                                      #
+//              noexcept (expression)
+//              ::= <template-param>
+//              ::= <function-param>
+//              ::= dt <expression> <unresolved-name>                    #
+//              expr.name
+//              ::= pt <expression> <unresolved-name>                    #
+//              expr->name
+//              ::= ds <expression> <expression>                         #
+//              expr.*expr
+//              ::= sZ <template-param>                                  # size
+//              of a parameter pack
+//              ::= sZ <function-param>                                  # size
+//              of a function parameter pack
+//              ::= sp <expression>                                      # pack
+//              expansion
+//              ::= tw <expression>                                      # throw
+//              expression
+//              ::= tr                                                   # throw
+//              with no operand (rethrow)
+//              ::= <unresolved-name>                                    # f(p),
+//              N::f(p), ::f(p),
+//                                                                       #
+//                                                                       freestanding
+//                                                                       dependent
+//                                                                       name
+//                                                                       (e.g.,
+//                                                                       T::x),
+//                                                                       #
+//                                                                       objectless
+//                                                                       nonstatic
+//                                                                       member
+//                                                                       reference
+//              ::= <expr-primary>
+
+template <class C>
+static const char *parse_expression(const char *first, const char *last,
+                                    C &db) {
+  if (last - first >= 2) {
+    const char *t = first;
+    bool parsed_gs = false;
+    if (last - first >= 4 && t[0] == 'g' && t[1] == 's') {
+      t += 2;
+      parsed_gs = true;
+    }
+    switch (*t) {
+    case 'L':
+      first = parse_expr_primary(first, last, db);
+      break;
+    case 'T':
+      first = parse_template_param(first, last, db);
+      break;
+    case 'f':
+      first = parse_function_param(first, last, db);
+      break;
+    case 'a':
+      switch (t[1]) {
+      case 'a':
+        t = parse_binary_expression(first + 2, last, "&&", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'd':
+        t = parse_prefix_expression(first + 2, last, "&", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'n':
+        t = parse_binary_expression(first + 2, last, "&", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'N':
+        t = parse_binary_expression(first + 2, last, "&=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'S':
+        t = parse_binary_expression(first + 2, last, "=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 't':
+        first = parse_alignof_type(first, last, db);
+        break;
+      case 'z':
+        first = parse_alignof_expr(first, last, db);
+        break;
+      }
+      break;
+    case 'c':
+      switch (t[1]) {
+      case 'c':
+        first = parse_const_cast_expr(first, last, db);
+        break;
+      case 'l':
+        first = parse_call_expr(first, last, db);
+        break;
+      case 'm':
+        t = parse_binary_expression(first + 2, last, ",", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'o':
+        t = parse_prefix_expression(first + 2, last, "~", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'v':
+        first = parse_conversion_expr(first, last, db);
+        break;
+      }
+      break;
+    case 'd':
+      switch (t[1]) {
+      case 'a': {
+        const char *t1 = parse_expression(t + 2, last, db);
+        if (t1 != t + 2) {
+          if (db.names.empty())
+            return first;
+          db.names.back().first =
+              (parsed_gs ? std::string("::") : std::string()) + "delete[] " +
+              db.names.back().move_full();
+          first = t1;
+        }
+      } break;
+      case 'c':
+        first = parse_dynamic_cast_expr(first, last, db);
+        break;
+      case 'e':
+        t = parse_prefix_expression(first + 2, last, "*", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'l': {
+        const char *t1 = parse_expression(t + 2, last, db);
+        if (t1 != t + 2) {
+          if (db.names.empty())
+            return first;
+          db.names.back().first =
+              (parsed_gs ? std::string("::") : std::string()) + "delete " +
+              db.names.back().move_full();
+          first = t1;
+        }
+      } break;
+      case 'n':
+        return parse_unresolved_name(first, last, db);
+      case 's':
+        first = parse_dot_star_expr(first, last, db);
+        break;
+      case 't':
+        first = parse_dot_expr(first, last, db);
+        break;
+      case 'v':
+        t = parse_binary_expression(first + 2, last, "/", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'V':
+        t = parse_binary_expression(first + 2, last, "/=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      }
+      break;
+    case 'e':
+      switch (t[1]) {
+      case 'o':
+        t = parse_binary_expression(first + 2, last, "^", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'O':
+        t = parse_binary_expression(first + 2, last, "^=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'q':
+        t = parse_binary_expression(first + 2, last, "==", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      }
+      break;
+    case 'g':
+      switch (t[1]) {
+      case 'e':
+        t = parse_binary_expression(first + 2, last, ">=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 't':
+        t = parse_binary_expression(first + 2, last, ">", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      }
+      break;
+    case 'i':
+      if (t[1] == 'x') {
+        const char *t1 = parse_expression(first + 2, last, db);
+        if (t1 != first + 2) {
+          const char *t2 = parse_expression(t1, last, db);
+          if (t2 != t1) {
+            if (db.names.size() < 2)
+              return first;
+            auto op2 = db.names.back().move_full();
+            db.names.pop_back();
+            auto op1 = db.names.back().move_full();
+            db.names.back() = "(" + op1 + ")[" + op2 + "]";
+            first = t2;
+          } else if (!db.names.empty())
+            db.names.pop_back();
+        }
+      }
+      break;
+    case 'l':
+      switch (t[1]) {
+      case 'e':
+        t = parse_binary_expression(first + 2, last, "<=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 's':
+        t = parse_binary_expression(first + 2, last, "<<", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'S':
+        t = parse_binary_expression(first + 2, last, "<<=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 't':
+        t = parse_binary_expression(first + 2, last, "<", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      }
+      break;
+    case 'm':
+      switch (t[1]) {
+      case 'i':
+        t = parse_binary_expression(first + 2, last, "-", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'I':
+        t = parse_binary_expression(first + 2, last, "-=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'l':
+        t = parse_binary_expression(first + 2, last, "*", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'L':
+        t = parse_binary_expression(first + 2, last, "*=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'm':
+        if (first + 2 != last && first[2] == '_') {
+          t = parse_prefix_expression(first + 3, last, "--", db);
+          if (t != first + 3)
+            first = t;
+        } else {
+          const char *t1 = parse_expression(first + 2, last, db);
+          if (t1 != first + 2) {
+            if (db.names.empty())
+              return first;
+            db.names.back() = "(" + db.names.back().move_full() + ")--";
+            first = t1;
+          }
+        }
+        break;
+      }
+      break;
+    case 'n':
+      switch (t[1]) {
+      case 'a':
+      case 'w':
+        first = parse_new_expr(first, last, db);
+        break;
+      case 'e':
+        t = parse_binary_expression(first + 2, last, "!=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'g':
+        t = parse_prefix_expression(first + 2, last, "-", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 't':
+        t = parse_prefix_expression(first + 2, last, "!", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'x':
+        t = parse_noexcept_expression(first + 2, last, db);
+        if (t != first + 2)
+          first = t;
+        break;
+      }
+      break;
+    case 'o':
+      switch (t[1]) {
+      case 'n':
+        return parse_unresolved_name(first, last, db);
+      case 'o':
+        t = parse_binary_expression(first + 2, last, "||", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'r':
+        t = parse_binary_expression(first + 2, last, "|", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'R':
+        t = parse_binary_expression(first + 2, last, "|=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      }
+      break;
+    case 'p':
+      switch (t[1]) {
+      case 'm':
+        t = parse_binary_expression(first + 2, last, "->*", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'l':
+        t = parse_binary_expression(first + 2, last, "+", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'L':
+        t = parse_binary_expression(first + 2, last, "+=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'p':
+        if (first + 2 != last && first[2] == '_') {
+          t = parse_prefix_expression(first + 3, last, "++", db);
+          if (t != first + 3)
+            first = t;
+        } else {
+          const char *t1 = parse_expression(first + 2, last, db);
+          if (t1 != first + 2) {
+            if (db.names.empty())
+              return first;
+            db.names.back() = "(" + db.names.back().move_full() + ")++";
+            first = t1;
+          }
+        }
+        break;
+      case 's':
+        t = parse_prefix_expression(first + 2, last, "+", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 't':
+        first = parse_arrow_expr(first, last, db);
+        break;
+      }
+      break;
+    case 'q':
+      if (t[1] == 'u') {
+        const char *t1 = parse_expression(first + 2, last, db);
+        if (t1 != first + 2) {
+          const char *t2 = parse_expression(t1, last, db);
+          if (t2 != t1) {
+            const char *t3 = parse_expression(t2, last, db);
+            if (t3 != t2) {
+              if (db.names.size() < 3)
+                return first;
+              auto op3 = db.names.back().move_full();
+              db.names.pop_back();
+              auto op2 = db.names.back().move_full();
+              db.names.pop_back();
+              auto op1 = db.names.back().move_full();
+              db.names.back() = "(" + op1 + ") ? (" + op2 + ") : (" + op3 + ")";
+              first = t3;
+            } else {
+              if (db.names.size() < 2)
+                return first;
+              db.names.pop_back();
+              db.names.pop_back();
+            }
+          } else if (!db.names.empty())
+            db.names.pop_back();
+        }
+      }
+      break;
+    case 'r':
+      switch (t[1]) {
+      case 'c':
+        first = parse_reinterpret_cast_expr(first, last, db);
+        break;
+      case 'm':
+        t = parse_binary_expression(first + 2, last, "%", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'M':
+        t = parse_binary_expression(first + 2, last, "%=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 's':
+        t = parse_binary_expression(first + 2, last, ">>", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      case 'S':
+        t = parse_binary_expression(first + 2, last, ">>=", db);
+        if (t != first + 2)
+          first = t;
+        break;
+      }
+      break;
+    case 's':
+      switch (t[1]) {
+      case 'c':
+        first = parse_static_cast_expr(first, last, db);
+        break;
+      case 'p':
+        first = parse_pack_expansion(first, last, db);
+        break;
+      case 'r':
+        return parse_unresolved_name(first, last, db);
+      case 't':
+        first = parse_sizeof_type_expr(first, last, db);
+        break;
+      case 'z':
+        first = parse_sizeof_expr_expr(first, last, db);
+        break;
+      case 'Z':
+        if (last - t >= 3) {
+          switch (t[2]) {
+          case 'T':
+            first = parse_sizeof_param_pack_expr(first, last, db);
+            break;
+          case 'f':
+            first = parse_sizeof_function_param_pack_expr(first, last, db);
+            break;
+          }
+        }
+        break;
+      }
+      break;
+    case 't':
+      switch (t[1]) {
+      case 'e':
+      case 'i':
+        first = parse_typeid_expr(first, last, db);
+        break;
+      case 'r':
+        db.names.push_back("throw");
+        first += 2;
+        break;
+      case 'w':
+        first = parse_throw_expr(first, last, db);
+        break;
+      }
+      break;
+    case '1':
+    case '2':
+    case '3':
+    case '4':
+    case '5':
+    case '6':
+    case '7':
+    case '8':
+    case '9':
+      return parse_unresolved_name(first, last, db);
+    }
+  }
+  return first;
+}
+
+// <template-arg> ::= <type>                                             # type
+// or template
+//                ::= X <expression> E                                   #
+//                expression
+//                ::= <expr-primary>                                     #
+//                simple expressions
+//                ::= J <template-arg>* E                                #
+//                argument pack
+//                ::= LZ <encoding> E                                    #
+//                extension
+
+template <class C>
+static const char *parse_template_arg(const char *first, const char *last,
+                                      C &db) {
+  if (first != last) {
+    const char *t;
+    switch (*first) {
+    case 'X':
+      t = parse_expression(first + 1, last, db);
+      if (t != first + 1) {
+        if (t != last && *t == 'E')
+          first = t + 1;
+      }
+      break;
+    case 'J':
+      t = first + 1;
+      if (t == last)
+        return first;
+      while (*t != 'E') {
+        const char *t1 = parse_template_arg(t, last, db);
+        if (t1 == t)
+          return first;
+        t = t1;
+      }
+      first = t + 1;
+      break;
+    case 'L':
+      // <expr-primary> or LZ <encoding> E
+      if (first + 1 != last && first[1] == 'Z') {
+        t = parse_encoding(first + 2, last, db);
+        if (t != first + 2 && t != last && *t == 'E')
+          first = t + 1;
+      } else
+        first = parse_expr_primary(first, last, db);
+      break;
+    default:
+      // <type>
+      first = parse_type(first, last, db);
+      break;
+    }
+  }
+  return first;
+}
+
+// <template-args> ::= I <template-arg>* E
+//     extension, the abi says <template-arg>+
+
+template <class C>
+static const char *parse_template_args(const char *first, const char *last,
+                                       C &db) {
+  if (last - first >= 2 && *first == 'I') {
+    if (db.tag_templates)
+      db.template_param.back().clear();
+    const char *t = first + 1;
+    std::string args("<");
+    while (*t != 'E') {
+      if (db.tag_templates)
+        db.template_param.emplace_back();
+      size_t k0 = db.names.size();
+      const char *t1 = parse_template_arg(t, last, db);
+      size_t k1 = db.names.size();
+      if (db.tag_templates)
+        db.template_param.pop_back();
+      if (t1 == t || t1 == last)
+        return first;
+      if (db.tag_templates) {
+        db.template_param.back().emplace_back();
+        for (size_t k = k0; k < k1; ++k)
+          db.template_param.back().back().push_back(db.names[k]);
+      }
+      for (size_t k = k0; k < k1; ++k) {
+        if (args.size() > 1)
+          args += ", ";
+        args += db.names[k].move_full();
+      }
+      for (; k1 > k0; --k1)
+        if (!db.names.empty())
+          db.names.pop_back();
+      t = t1;
+    }
+    first = t + 1;
+    if (args.back() != '>')
+      args += ">";
+    else
+      args += " >";
+    db.names.push_back(std::move(args));
+  }
+  return first;
+}
+
+// <nested-name> ::= N [<CV-qualifiers>] [<ref-qualifier>] <prefix>
+// <unqualified-name> E
+//               ::= N [<CV-qualifiers>] [<ref-qualifier>] <template-prefix>
+//               <template-args> E
+//
+// <prefix> ::= <prefix> <unqualified-name>
+//          ::= <template-prefix> <template-args>
+//          ::= <template-param>
+//          ::= <decltype>
+//          ::= # empty
+//          ::= <substitution>
+//          ::= <prefix> <data-member-prefix>
+//  extension ::= L
+//
+// <template-prefix> ::= <prefix> <template unqualified-name>
+//                   ::= <template-param>
+//                   ::= <substitution>
+
+template <class C>
+static const char *parse_nested_name(const char *first, const char *last, C &db,
+                                     bool *ends_with_template_args) {
+  if (first != last && *first == 'N') {
+    unsigned cv;
+    const char *t0 = parse_cv_qualifiers(first + 1, last, cv);
+    if (t0 == last)
+      return first;
+    db.ref = 0;
+    if (*t0 == 'R') {
+      db.ref = 1;
+      ++t0;
+    } else if (*t0 == 'O') {
+      db.ref = 2;
+      ++t0;
+    }
+    db.names.emplace_back();
+    if (last - t0 >= 2 && t0[0] == 'S' && t0[1] == 't') {
+      t0 += 2;
+      db.names.back().first = "std";
+    }
+    if (t0 == last) {
+      db.names.pop_back();
+      return first;
+    }
+    bool pop_subs = false;
+    bool component_ends_with_template_args = false;
+    while (*t0 != 'E') {
+      component_ends_with_template_args = false;
+      const char *t1;
+      switch (*t0) {
+      case 'S':
+        if (t0 + 1 != last && t0[1] == 't')
+          goto do_parse_unqualified_name;
+        t1 = parse_substitution(t0, last, db);
+        if (t1 != t0 && t1 != last) {
+          auto name = db.names.back().move_full();
+          db.names.pop_back();
+          if (db.names.empty())
+            return first;
+          if (!db.names.back().first.empty()) {
+            db.names.back().first += "::" + name;
+            db.subs.push_back(typename C::sub_type(1, db.names.back()));
+          } else
+            db.names.back().first = name;
+          pop_subs = true;
+          t0 = t1;
+        } else
+          return first;
+        break;
+      case 'T':
+        t1 = parse_template_param(t0, last, db);
+        if (t1 != t0 && t1 != last) {
+          auto name = db.names.back().move_full();
+          db.names.pop_back();
+          if (db.names.empty())
+            return first;
+          if (!db.names.back().first.empty())
+            db.names.back().first += "::" + name;
+          else
+            db.names.back().first = name;
+          db.subs.push_back(typename C::sub_type(1, db.names.back()));
+          pop_subs = true;
+          t0 = t1;
+        } else
+          return first;
+        break;
+      case 'D':
+        if (t0 + 1 != last && t0[1] != 't' && t0[1] != 'T')
+          goto do_parse_unqualified_name;
+        t1 = parse_decltype(t0, last, db);
+        if (t1 != t0 && t1 != last) {
+          auto name = db.names.back().move_full();
+          db.names.pop_back();
+          if (db.names.empty())
+            return first;
+          if (!db.names.back().first.empty())
+            db.names.back().first += "::" + name;
+          else
+            db.names.back().first = name;
+          db.subs.push_back(typename C::sub_type(1, db.names.back()));
+          pop_subs = true;
+          t0 = t1;
+        } else
+          return first;
+        break;
+      case 'I':
+        t1 = parse_template_args(t0, last, db);
+        if (t1 != t0 && t1 != last) {
+          auto name = db.names.back().move_full();
+          db.names.pop_back();
+          if (db.names.empty())
+            return first;
+          db.names.back().first += name;
+          db.subs.push_back(typename C::sub_type(1, db.names.back()));
+          t0 = t1;
+          component_ends_with_template_args = true;
+        } else
+          return first;
+        break;
+      case 'L':
+        if (++t0 == last)
+          return first;
+        break;
+      default:
+      do_parse_unqualified_name:
+        t1 = parse_unqualified_name(t0, last, db);
+        if (t1 != t0 && t1 != last) {
+          auto name = db.names.back().move_full();
+          db.names.pop_back();
+          if (db.names.empty())
+            return first;
+          if (!db.names.back().first.empty())
+            db.names.back().first += "::" + name;
+          else
+            db.names.back().first = name;
+          db.subs.push_back(typename C::sub_type(1, db.names.back()));
+          pop_subs = true;
+          t0 = t1;
+        } else
+          return first;
+      }
+    }
+    first = t0 + 1;
+    db.cv = cv;
+    if (pop_subs && !db.subs.empty())
+      db.subs.pop_back();
+    if (ends_with_template_args)
+      *ends_with_template_args = component_ends_with_template_args;
+  }
+  return first;
+}
+
+// <discriminator> := _ <non-negative number>      # when number < 10
+//                 := __ <non-negative number> _   # when number >= 10
+//  extension      := decimal-digit+               # at the end of string
+
+static const char *parse_discriminator(const char *first, const char *last) {
+  // parse but ignore discriminator
+  if (first != last) {
+    if (*first == '_') {
+      const char *t1 = first + 1;
+      if (t1 != last) {
+        if (std::isdigit(*t1))
+          first = t1 + 1;
+        else if (*t1 == '_') {
+          for (++t1; t1 != last && std::isdigit(*t1); ++t1)
+            ;
+          if (t1 != last && *t1 == '_')
+            first = t1 + 1;
+        }
+      }
+    } else if (std::isdigit(*first)) {
+      const char *t1 = first + 1;
+      for (; t1 != last && std::isdigit(*t1); ++t1)
+        ;
+      if (t1 == last)
+        first = last;
+    }
+  }
+  return first;
+}
+
+// <local-name> := Z <function encoding> E <entity name> [<discriminator>]
+//              := Z <function encoding> E s [<discriminator>]
+//              := Z <function encoding> Ed [ <parameter number> ] _ <entity
+//              name>
+
+template <class C>
+static const char *parse_local_name(const char *first, const char *last, C &db,
+                                    bool *ends_with_template_args) {
+  if (first != last && *first == 'Z') {
+    const char *t = parse_encoding(first + 1, last, db);
+    if (t != first + 1 && t != last && *t == 'E' && ++t != last) {
+      switch (*t) {
+      case 's':
+        first = parse_discriminator(t + 1, last);
+        if (db.names.empty())
+          return first;
+        db.names.back().first.append("::string literal");
+        break;
+      case 'd':
+        if (++t != last) {
+          const char *t1 = parse_number(t, last);
+          if (t1 != last && *t1 == '_') {
+            t = t1 + 1;
+            t1 = parse_name(t, last, db, ends_with_template_args);
+            if (t1 != t) {
+              if (db.names.size() < 2)
+                return first;
+              auto name = db.names.back().move_full();
+              db.names.pop_back();
+              if (db.names.empty())
+                return first;
+              db.names.back().first.append("::");
+              db.names.back().first.append(name);
+              first = t1;
+            } else if (!db.names.empty())
+              db.names.pop_back();
+          }
+        }
+        break;
+      default: {
+        const char *t1 = parse_name(t, last, db, ends_with_template_args);
+        if (t1 != t) {
+          // parse but ignore discriminator
+          first = parse_discriminator(t1, last);
+          if (db.names.size() < 2)
+            return first;
+          auto name = db.names.back().move_full();
+          db.names.pop_back();
+          if (db.names.empty())
+            return first;
+          db.names.back().first.append("::");
+          db.names.back().first.append(name);
+        } else if (!db.names.empty())
+          db.names.pop_back();
+      } break;
+      }
+    }
+  }
+  return first;
+}
+
+// <name> ::= <nested-name> // N
+//        ::= <local-name> # See Scope Encoding below  // Z
+//        ::= <unscoped-template-name> <template-args>
+//        ::= <unscoped-name>
+
+// <unscoped-template-name> ::= <unscoped-name>
+//                          ::= <substitution>
+
+template <class C>
+static const char *parse_name(const char *first, const char *last, C &db,
+                              bool *ends_with_template_args) {
+  if (last - first >= 2) {
+    const char *t0 = first;
+    // extension: ignore L here
+    if (*t0 == 'L')
+      ++t0;
+    switch (*t0) {
+    case 'N': {
+      const char *t1 = parse_nested_name(t0, last, db, ends_with_template_args);
+      if (t1 != t0)
+        first = t1;
+      break;
+    }
+    case 'Z': {
+      const char *t1 = parse_local_name(t0, last, db, ends_with_template_args);
+      if (t1 != t0)
+        first = t1;
+      break;
+    }
+    default: {
+      const char *t1 = parse_unscoped_name(t0, last, db);
+      if (t1 != t0) {
+        if (t1 != last &&
+            *t1 == 'I') // <unscoped-template-name> <template-args>
+        {
+          if (db.names.empty())
+            return first;
+          db.subs.push_back(typename C::sub_type(1, db.names.back()));
+          t0 = t1;
+          t1 = parse_template_args(t0, last, db);
+          if (t1 != t0) {
+            if (db.names.size() < 2)
+              return first;
+            auto tmp = db.names.back().move_full();
+            db.names.pop_back();
+            if (db.names.empty())
+              return first;
+            db.names.back().first += tmp;
+            first = t1;
+            if (ends_with_template_args)
+              *ends_with_template_args = true;
+          }
+        } else // <unscoped-name>
+          first = t1;
+      } else { // try <substitution> <template-args>
+        t1 = parse_substitution(t0, last, db);
+        if (t1 != t0 && t1 != last && *t1 == 'I') {
+          t0 = t1;
+          t1 = parse_template_args(t0, last, db);
+          if (t1 != t0) {
+            if (db.names.size() < 2)
+              return first;
+            auto tmp = db.names.back().move_full();
+            db.names.pop_back();
+            if (db.names.empty())
+              return first;
+            db.names.back().first += tmp;
+            first = t1;
+            if (ends_with_template_args)
+              *ends_with_template_args = true;
+          }
+        }
+      }
+      break;
+    }
+    }
+  }
+  return first;
+}
+
+// <call-offset> ::= h <nv-offset> _
+//               ::= v <v-offset> _
+//
+// <nv-offset> ::= <offset number>
+//               # non-virtual base override
+//
+// <v-offset>  ::= <offset number> _ <virtual offset number>
+//               # virtual base override, with vcall offset
+
+static const char *parse_call_offset(const char *first, const char *last) {
+  if (first != last) {
+    switch (*first) {
+    case 'h': {
+      const char *t = parse_number(first + 1, last);
+      if (t != first + 1 && t != last && *t == '_')
+        first = t + 1;
+    } break;
+    case 'v': {
+      const char *t = parse_number(first + 1, last);
+      if (t != first + 1 && t != last && *t == '_') {
+        const char *t2 = parse_number(++t, last);
+        if (t2 != t && t2 != last && *t2 == '_')
+          first = t2 + 1;
+      }
+    } break;
+    }
+  }
+  return first;
+}
+
+// <special-name> ::= TV <type>    # virtual table
+//                ::= TT <type>    # VTT structure (construction vtable index)
+//                ::= TI <type>    # typeinfo structure
+//                ::= TS <type>    # typeinfo name (null-terminated byte string)
+//                ::= Tc <call-offset> <call-offset> <base encoding>
+//                    # base is the nominal target function of thunk
+//                    # first call-offset is 'this' adjustment
+//                    # second call-offset is result adjustment
+//                ::= T <call-offset> <base encoding>
+//                    # base is the nominal target function of thunk
+//                ::= GV <object name> # Guard variable for one-time
+//                initialization
+//                                     # No <type>
+//      extension ::= TC <first type> <number> _ <second type> # construction
+//      vtable for second-in-first
+//      extension ::= GR <object name> # reference temporary for object
+
+template <class C>
+static const char *parse_special_name(const char *first, const char *last,
+                                      C &db) {
+  if (last - first > 2) {
+    const char *t;
+    switch (*first) {
+    case 'T':
+      switch (first[1]) {
+      case 'V':
+        // TV <type>    # virtual table
+        t = parse_type(first + 2, last, db);
+        if (t != first + 2) {
+          if (db.names.empty())
+            return first;
+          db.names.back().first.insert(0, "vtable for ");
+          first = t;
+        }
+        break;
+      case 'T':
+        // TT <type>    # VTT structure (construction vtable index)
+        t = parse_type(first + 2, last, db);
+        if (t != first + 2) {
+          if (db.names.empty())
+            return first;
+          db.names.back().first.insert(0, "VTT for ");
+          first = t;
+        }
+        break;
+      case 'I':
+        // TI <type>    # typeinfo structure
+        t = parse_type(first + 2, last, db);
+        if (t != first + 2) {
+          if (db.names.empty())
+            return first;
+          db.names.back().first.insert(0, "typeinfo for ");
+          first = t;
+        }
+        break;
+      case 'S':
+        // TS <type>    # typeinfo name (null-terminated byte string)
+        t = parse_type(first + 2, last, db);
+        if (t != first + 2) {
+          if (db.names.empty())
+            return first;
+          db.names.back().first.insert(0, "typeinfo name for ");
+          first = t;
+        }
+        break;
+      case 'c':
+        // Tc <call-offset> <call-offset> <base encoding>
+        {
+          const char *t0 = parse_call_offset(first + 2, last);
+          if (t0 == first + 2)
+            break;
+          const char *t1 = parse_call_offset(t0, last);
+          if (t1 == t0)
+            break;
+          t = parse_encoding(t1, last, db);
+          if (t != t1) {
+            if (db.names.empty())
+              return first;
+            db.names.back().first.insert(0, "covariant return thunk to ");
+            first = t;
+          }
+        }
+        break;
+      case 'C':
+        // extension ::= TC <first type> <number> _ <second type> # construction
+        // vtable for second-in-first
+        t = parse_type(first + 2, last, db);
+        if (t != first + 2) {
+          const char *t0 = parse_number(t, last);
+          if (t0 != t && t0 != last && *t0 == '_') {
+            const char *t1 = parse_type(++t0, last, db);
+            if (t1 != t0) {
+              if (db.names.size() < 2)
+                return first;
+              auto left = db.names.back().move_full();
+              db.names.pop_back();
+              if (db.names.empty())
+                return first;
+              db.names.back().first = "construction vtable for " +
+                                      std::move(left) + "-in-" +
+                                      db.names.back().move_full();
+              first = t1;
+            }
+          }
+        }
+        break;
+      default:
+        // T <call-offset> <base encoding>
+        {
+          const char *t0 = parse_call_offset(first + 1, last);
+          if (t0 == first + 1)
+            break;
+          t = parse_encoding(t0, last, db);
+          if (t != t0) {
+            if (db.names.empty())
+              return first;
+            if (first[1] == 'v') {
+              db.names.back().first.insert(0, "virtual thunk to ");
+              first = t;
+            } else {
+              db.names.back().first.insert(0, "non-virtual thunk to ");
+              first = t;
+            }
+          }
+        }
+        break;
+      }
+      break;
+    case 'G':
+      switch (first[1]) {
+      case 'V':
+        // GV <object name> # Guard variable for one-time initialization
+        t = parse_name(first + 2, last, db);
+        if (t != first + 2) {
+          if (db.names.empty())
+            return first;
+          db.names.back().first.insert(0, "guard variable for ");
+          first = t;
+        }
+        break;
+      case 'R':
+        // extension ::= GR <object name> # reference temporary for object
+        t = parse_name(first + 2, last, db);
+        if (t != first + 2) {
+          if (db.names.empty())
+            return first;
+          db.names.back().first.insert(0, "reference temporary for ");
+          first = t;
+        }
+        break;
+      }
+      break;
+    }
+  }
+  return first;
+}
+
+namespace {
+template <class T> class save_value {
+  T &restore_;
+  T original_value_;
+
+public:
+  save_value(T &restore) : restore_(restore), original_value_(restore) {}
+
+  ~save_value() { restore_ = std::move(original_value_); }
+
+  save_value(const save_value &) = delete;
+  save_value &operator=(const save_value &) = delete;
+};
+}
+
+// <encoding> ::= <function name> <bare-function-type>
+//            ::= <data name>
+//            ::= <special-name>
+
+template <class C>
+static const char *parse_encoding(const char *first, const char *last, C &db) {
+  if (first != last) {
+    save_value<decltype(db.encoding_depth)> su(db.encoding_depth);
+    ++db.encoding_depth;
+    save_value<decltype(db.tag_templates)> sb(db.tag_templates);
+    if (db.encoding_depth > 1)
+      db.tag_templates = true;
+    switch (*first) {
+    case 'G':
+    case 'T':
+      first = parse_special_name(first, last, db);
+      break;
+    default: {
+      bool ends_with_template_args = false;
+      const char *t = parse_name(first, last, db, &ends_with_template_args);
+      unsigned cv = db.cv;
+      unsigned ref = db.ref;
+      if (t != first) {
+        if (t != last && *t != 'E' && *t != '.') {
+          save_value<bool> sb2(db.tag_templates);
+          db.tag_templates = false;
+          const char *t2;
+          std::string ret2;
+          if (db.names.empty())
+            return first;
+          const std::string &nm = db.names.back().first;
+          if (nm.empty())
+            return first;
+          if (!db.parsed_ctor_dtor_cv && ends_with_template_args) {
+            t2 = parse_type(t, last, db);
+            if (t2 == t)
+              return first;
+            if (db.names.size() < 2)
+              return first;
+            auto ret1 = std::move(db.names.back().first);
+            ret2 = std::move(db.names.back().second);
+            if (ret2.empty())
+              ret1 += ' ';
+            db.names.pop_back();
+            if (db.names.empty())
+              return first;
+
+            db.names.back().first.insert(0, ret1);
+            t = t2;
+          }
+          db.names.back().first += '(';
+          if (t != last && *t == 'v') {
+            ++t;
+          } else {
+            bool first_arg = true;
+            while (true) {
+              size_t k0 = db.names.size();
+              t2 = parse_type(t, last, db);
+              size_t k1 = db.names.size();
+              if (t2 == t)
+                break;
+              if (k1 > k0) {
+                std::string tmp;
+                for (size_t k = k0; k < k1; ++k) {
+                  if (!tmp.empty())
+                    tmp += ", ";
+                  tmp += db.names[k].move_full();
+                }
+                for (size_t k = k0; k < k1; ++k) {
+                  if (db.names.empty())
+                    return first;
+                  db.names.pop_back();
+                }
+                if (!tmp.empty()) {
+                  if (db.names.empty())
+                    return first;
+                  if (!first_arg)
+                    db.names.back().first += ", ";
+                  else
+                    first_arg = false;
+                  db.names.back().first += tmp;
+                }
+              }
+              t = t2;
+            }
+          }
+          if (db.names.empty())
+            return first;
+          db.names.back().first += ')';
+          if (cv & 1)
+            db.names.back().first.append(" const");
+          if (cv & 2)
+            db.names.back().first.append(" volatile");
+          if (cv & 4)
+            db.names.back().first.append(" restrict");
+          if (ref == 1)
+            db.names.back().first.append(" &");
+          else if (ref == 2)
+            db.names.back().first.append(" &&");
+          db.names.back().first += ret2;
+          first = t;
+        } else
+          first = t;
+      }
+      break;
+    }
+    }
+  }
+  return first;
+}
+
+// _block_invoke
+// _block_invoke<decimal-digit>+
+// _block_invoke_<decimal-digit>+
+
+template <class C>
+static const char *parse_block_invoke(const char *first, const char *last,
+                                      C &db) {
+  if (last - first >= 13) {
+    const char test[] = "_block_invoke";
+    const char *t = first;
+    for (int i = 0; i < 13; ++i, ++t) {
+      if (*t != test[i])
+        return first;
+    }
+    if (t != last) {
+      if (*t == '_') {
+        // must have at least 1 decimal digit
+        if (++t == last || !std::isdigit(*t))
+          return first;
+        ++t;
+      }
+      // parse zero or more digits
+      while (t != last && isdigit(*t))
+        ++t;
+    }
+    if (db.names.empty())
+      return first;
+    db.names.back().first.insert(0, "invocation function for block in ");
+    first = t;
+  }
+  return first;
+}
+
+// extension
+// <dot-suffix> := .<anything and everything>
+
+template <class C>
+static const char *parse_dot_suffix(const char *first, const char *last,
+                                    C &db) {
+  if (first != last && *first == '.') {
+    if (db.names.empty())
+      return first;
+    db.names.back().first += " (" + std::string(first, last) + ")";
+    first = last;
+  }
+  return first;
+}
+
+// <block-involcaton-function> ___Z<encoding>_block_invoke
+// <block-involcaton-function> ___Z<encoding>_block_invoke<decimal-digit>+
+// <block-involcaton-function> ___Z<encoding>_block_invoke_<decimal-digit>+
+// <mangled-name> ::= _Z<encoding>
+//                ::= <type>
+
+template <class C>
+static void demangle(const char *first, const char *last, C &db, int &status) {
+  if (first >= last) {
+    status = invalid_mangled_name;
+    return;
+  }
+  if (*first == '_') {
+    if (last - first >= 4) {
+      if (first[1] == 'Z') {
+        const char *t = parse_encoding(first + 2, last, db);
+        if (t != first + 2 && t != last && *t == '.')
+          t = parse_dot_suffix(t, last, db);
+        if (t != last)
+          status = invalid_mangled_name;
+      } else if (first[1] == '_' && first[2] == '_' && first[3] == 'Z') {
+        const char *t = parse_encoding(first + 4, last, db);
+        if (t != first + 4 && t != last) {
+          const char *t1 = parse_block_invoke(t, last, db);
+          if (t1 != last)
+            status = invalid_mangled_name;
+        } else
+          status = invalid_mangled_name;
+      } else
+        status = invalid_mangled_name;
+    } else
+      status = invalid_mangled_name;
+  } else {
+    const char *t = parse_type(first, last, db);
+    if (t != last)
+      status = invalid_mangled_name;
+  }
+  if (status == success && db.names.empty())
+    status = invalid_mangled_name;
+}
+
+namespace {
+template <class StrT> struct string_pair {
+  StrT first;
+  StrT second;
+
+  string_pair() = default;
+  string_pair(StrT f) : first(std::move(f)) {}
+  string_pair(StrT f, StrT s) : first(std::move(f)), second(std::move(s)) {}
+  template <size_t N> string_pair(const char (&s)[N]) : first(s, N - 1) {}
+
+  size_t size() const { return first.size() + second.size(); }
+  StrT full() const { return first + second; }
+  StrT move_full() { return std::move(first) + std::move(second); }
+};
+
+struct Db {
+  typedef std::vector<string_pair<std::string>> sub_type;
+  typedef std::vector<sub_type> template_param_type;
+  sub_type names;
+  template_param_type subs;
+  std::vector<template_param_type> template_param;
+  unsigned cv = 0;
+  unsigned ref = 0;
+  unsigned encoding_depth = 0;
+  bool parsed_ctor_dtor_cv = false;
+  bool tag_templates = true;
+  bool fix_forward_references = false;
+  bool try_to_parse_template_args = true;
+
+  Db() : subs(0, names), template_param(0, subs) {}
+};
+}
+
+char *llvm::itaniumDemangle(const char *mangled_name, char *buf, size_t *n,
+                            int *status) {
+  if (mangled_name == nullptr || (buf != nullptr && n == nullptr)) {
+    if (status)
+      *status = invalid_args;
+    return nullptr;
+  }
+
+  size_t len = std::strlen(mangled_name);
+  if (len < 2 || strncmp(mangled_name, "_Z", 2)) {
+    if (len < 4 || strncmp(mangled_name, "___Z", 4)) {
+      if (status)
+        *status = invalid_mangled_name;
+      return nullptr;
+    }
+  }
+
+  size_t internal_size = buf != nullptr ? *n : 0;
+  Db db;
+  db.template_param.emplace_back();
+  int internal_status = success;
+  demangle(mangled_name, mangled_name + len, db, internal_status);
+  if (internal_status == success && db.fix_forward_references &&
+      !db.template_param.empty() && !db.template_param.front().empty()) {
+    db.fix_forward_references = false;
+    db.tag_templates = false;
+    db.names.clear();
+    db.subs.clear();
+    demangle(mangled_name, mangled_name + len, db, internal_status);
+    if (db.fix_forward_references)
+      internal_status = invalid_mangled_name;
+  }
+  if (internal_status == success) {
+    size_t sz = db.names.back().size() + 1;
+    if (sz > internal_size) {
+      char *newbuf = static_cast<char *>(std::realloc(buf, sz));
+      if (newbuf == nullptr) {
+        internal_status = memory_alloc_failure;
+        buf = nullptr;
+      } else {
+        buf = newbuf;
+        if (n != nullptr)
+          *n = sz;
+      }
+    }
+    if (buf != nullptr) {
+      db.names.back().first += db.names.back().second;
+      std::memcpy(buf, db.names.back().first.data(), sz - 1);
+      buf[sz - 1] = char(0);
+    }
+  } else
+    buf = nullptr;
+  if (status)
+    *status = internal_status;
+  return buf;
+}