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, 463 insertions, 173 deletions

diff --git a/contrib/llvm/lib/Object/Archive.cpp b/contrib/llvm/lib/Object/Archive.cpp
index daf301e..f2021f7 100644
--- a/contrib/llvm/lib/Object/Archive.cpp
+++ b/contrib/llvm/lib/Object/Archive.cpp
@@ -27,125 +27,380 @@ static const char *const ThinMagic = "!<thin>\n";
 
 void Archive::anchor() { }
 
-StringRef ArchiveMemberHeader::getName() const {
+static Error
+malformedError(Twine Msg) {
+  std::string StringMsg = "truncated or malformed archive (" + Msg.str() + ")";
+  return make_error<GenericBinaryError>(std::move(StringMsg),
+                                        object_error::parse_failed);
+}
+
+ArchiveMemberHeader::ArchiveMemberHeader(const Archive *Parent,
+                                         const char *RawHeaderPtr,
+                                         uint64_t Size, Error *Err)
+    : Parent(Parent),
+      ArMemHdr(reinterpret_cast<const ArMemHdrType *>(RawHeaderPtr)) {
+  if (RawHeaderPtr == nullptr)
+    return;
+  ErrorAsOutParameter ErrAsOutParam(Err);
+
+  if (Size < sizeof(ArMemHdrType)) {
+    if (Err) {
+      std::string Msg("remaining size of archive too small for next archive "
+                      "member header ");
+      Expected<StringRef> NameOrErr = getName(Size);
+      if (!NameOrErr) {
+        consumeError(NameOrErr.takeError());
+        uint64_t Offset = RawHeaderPtr - Parent->getData().data();
+        *Err = malformedError(Msg + "at offset " + Twine(Offset));
+      } else
+        *Err = malformedError(Msg + "for " + NameOrErr.get());
+    }
+    return;
+  }
+  if (ArMemHdr->Terminator[0] != '`' || ArMemHdr->Terminator[1] != '\n') {
+    if (Err) {
+      std::string Buf;
+      raw_string_ostream OS(Buf);
+      OS.write_escaped(llvm::StringRef(ArMemHdr->Terminator,
+                                       sizeof(ArMemHdr->Terminator)));
+      OS.flush();
+      std::string Msg("terminator characters in archive member \"" + Buf +
+                      "\" not the correct \"`\\n\" values for the archive "
+                      "member header ");
+      Expected<StringRef> NameOrErr = getName(Size);
+      if (!NameOrErr) {
+        consumeError(NameOrErr.takeError());
+        uint64_t Offset = RawHeaderPtr - Parent->getData().data();
+        *Err = malformedError(Msg + "at offset " + Twine(Offset));
+      } else
+        *Err = malformedError(Msg + "for " + NameOrErr.get());
+    }
+    return;
+  }
+}
+
+// This gets the raw name from the ArMemHdr->Name field and checks that it is
+// valid for the kind of archive.  If it is not valid it returns an Error.
+Expected<StringRef> ArchiveMemberHeader::getRawName() const {
   char EndCond;
-  if (Name[0] == '/' || Name[0] == '#')
+  auto Kind = Parent->kind();
+  if (Kind == Archive::K_BSD || Kind == Archive::K_DARWIN64) {
+    if (ArMemHdr->Name[0] == ' ') {
+      uint64_t Offset = reinterpret_cast<const char *>(ArMemHdr) -
+                        Parent->getData().data();
+      return malformedError("name contains a leading space for archive member "
+                            "header at offset " + Twine(Offset));
+    }
+    EndCond = ' ';
+  }
+  else if (ArMemHdr->Name[0] == '/' || ArMemHdr->Name[0] == '#')
     EndCond = ' ';
   else
     EndCond = '/';
   llvm::StringRef::size_type end =
-      llvm::StringRef(Name, sizeof(Name)).find(EndCond);
+      llvm::StringRef(ArMemHdr->Name, sizeof(ArMemHdr->Name)).find(EndCond);
   if (end == llvm::StringRef::npos)
-    end = sizeof(Name);
-  assert(end <= sizeof(Name) && end > 0);
+    end = sizeof(ArMemHdr->Name);
+  assert(end <= sizeof(ArMemHdr->Name) && end > 0);
   // Don't include the EndCond if there is one.
-  return llvm::StringRef(Name, end);
+  return llvm::StringRef(ArMemHdr->Name, end);
 }
 
-ErrorOr<uint32_t> ArchiveMemberHeader::getSize() const {
+// This gets the name looking up long names. Size is the size of the archive
+// member including the header, so the size of any name following the header
+// is checked to make sure it does not overflow.
+Expected<StringRef> ArchiveMemberHeader::getName(uint64_t Size) const {
+
+  // This can be called from the ArchiveMemberHeader constructor when the
+  // archive header is truncated to produce an error message with the name.
+  // Make sure the name field is not truncated.
+  if (Size < offsetof(ArMemHdrType, Name) + sizeof(ArMemHdr->Name)) {
+    uint64_t ArchiveOffset = reinterpret_cast<const char *>(ArMemHdr) -
+                      Parent->getData().data();
+    return malformedError("archive header truncated before the name field "
+                          "for archive member header at offset " +
+                          Twine(ArchiveOffset));
+  }
+
+  // The raw name itself can be invalid.
+  Expected<StringRef> NameOrErr = getRawName();
+  if (!NameOrErr)
+    return NameOrErr.takeError();
+  StringRef Name = NameOrErr.get();
+
+  // Check if it's a special name.
+  if (Name[0] == '/') {
+    if (Name.size() == 1) // Linker member.
+      return Name;
+    if (Name.size() == 2 && Name[1] == '/') // String table.
+      return Name;
+    // It's a long name.
+    // Get the string table offset.
+    std::size_t StringOffset;
+    if (Name.substr(1).rtrim(' ').getAsInteger(10, StringOffset)) {
+      std::string Buf;
+      raw_string_ostream OS(Buf);
+      OS.write_escaped(Name.substr(1).rtrim(' '));
+      OS.flush();
+      uint64_t ArchiveOffset = reinterpret_cast<const char *>(ArMemHdr) -
+                               Parent->getData().data();
+      return malformedError("long name offset characters after the '/' are "
+                            "not all decimal numbers: '" + Buf + "' for "
+                            "archive member header at offset " +
+                            Twine(ArchiveOffset));
+    }
+
+    // Verify it.
+    if (StringOffset >= Parent->getStringTable().size()) {
+      uint64_t ArchiveOffset = reinterpret_cast<const char *>(ArMemHdr) -
+                               Parent->getData().data();
+      return malformedError("long name offset " + Twine(StringOffset) + " past "
+                            "the end of the string table for archive member "
+                            "header at offset " + Twine(ArchiveOffset));
+    }
+    const char *addr = Parent->getStringTable().begin() + StringOffset;
+
+    // GNU long file names end with a "/\n".
+    if (Parent->kind() == Archive::K_GNU ||
+        Parent->kind() == Archive::K_MIPS64) {
+      StringRef::size_type End = StringRef(addr).find('\n');
+      return StringRef(addr, End - 1);
+    }
+    return addr;
+  }
+
+  if (Name.startswith("#1/")) {
+    uint64_t NameLength;
+    if (Name.substr(3).rtrim(' ').getAsInteger(10, NameLength)) {
+      std::string Buf;
+      raw_string_ostream OS(Buf);
+      OS.write_escaped(Name.substr(3).rtrim(' '));
+      OS.flush();
+      uint64_t ArchiveOffset = reinterpret_cast<const char *>(ArMemHdr) -
+                        Parent->getData().data();
+      return malformedError("long name length characters after the #1/ are "
+                            "not all decimal numbers: '" + Buf + "' for "
+                            "archive member header at offset " +
+                            Twine(ArchiveOffset));
+    }
+    if (getSizeOf() + NameLength > Size) {
+      uint64_t ArchiveOffset = reinterpret_cast<const char *>(ArMemHdr) -
+                        Parent->getData().data();
+      return malformedError("long name length: " + Twine(NameLength) +
+                            " extends past the end of the member or archive "
+                            "for archive member header at offset " +
+                            Twine(ArchiveOffset));
+    }
+    return StringRef(reinterpret_cast<const char *>(ArMemHdr) + getSizeOf(),
+                     NameLength).rtrim('\0');
+  }
+
+  // It is not a long name so trim the blanks at the end of the name.
+  if (Name[Name.size() - 1] != '/')
+    return Name.rtrim(' ');
+
+  // It's a simple name.
+  return Name.drop_back(1);
+}
+
+Expected<uint32_t> ArchiveMemberHeader::getSize() const {
   uint32_t Ret;
-  if (llvm::StringRef(Size, sizeof(Size)).rtrim(" ").getAsInteger(10, Ret))
-    return object_error::parse_failed; // Size is not a decimal number.
+  if (llvm::StringRef(ArMemHdr->Size,
+        sizeof(ArMemHdr->Size)).rtrim(" ").getAsInteger(10, Ret)) {
+    std::string Buf;
+    raw_string_ostream OS(Buf);
+    OS.write_escaped(llvm::StringRef(ArMemHdr->Size,
+                                     sizeof(ArMemHdr->Size)).rtrim(" "));
+    OS.flush();
+    uint64_t Offset = reinterpret_cast<const char *>(ArMemHdr) -
+                      Parent->getData().data();
+    return malformedError("characters in size field in archive header are not "
+                          "all decimal numbers: '" + Buf + "' for archive "
+                          "member header at offset " + Twine(Offset));
+  }
   return Ret;
 }
 
-sys::fs::perms ArchiveMemberHeader::getAccessMode() const {
+Expected<sys::fs::perms> ArchiveMemberHeader::getAccessMode() const {
   unsigned Ret;
-  if (StringRef(AccessMode, sizeof(AccessMode)).rtrim(' ').getAsInteger(8, Ret))
-    llvm_unreachable("Access mode is not an octal number.");
+  if (StringRef(ArMemHdr->AccessMode,
+                sizeof(ArMemHdr->AccessMode)).rtrim(' ').getAsInteger(8, Ret)) {
+    std::string Buf;
+    raw_string_ostream OS(Buf);
+    OS.write_escaped(llvm::StringRef(ArMemHdr->AccessMode,
+                                   sizeof(ArMemHdr->AccessMode)).rtrim(" "));
+    OS.flush();
+    uint64_t Offset = reinterpret_cast<const char *>(ArMemHdr) -
+                      Parent->getData().data();
+    return malformedError("characters in AccessMode field in archive header "
+                          "are not all decimal numbers: '" + Buf + "' for the "
+                          "archive member header at offset " + Twine(Offset));
+  }
   return static_cast<sys::fs::perms>(Ret);
 }
 
-sys::TimeValue ArchiveMemberHeader::getLastModified() const {
+Expected<sys::TimePoint<std::chrono::seconds>>
+ArchiveMemberHeader::getLastModified() const {
   unsigned Seconds;
-  if (StringRef(LastModified, sizeof(LastModified)).rtrim(' ')
-          .getAsInteger(10, Seconds))
-    llvm_unreachable("Last modified time not a decimal number.");
+  if (StringRef(ArMemHdr->LastModified,
+                sizeof(ArMemHdr->LastModified)).rtrim(' ')
+          .getAsInteger(10, Seconds)) {
+    std::string Buf;
+    raw_string_ostream OS(Buf);
+    OS.write_escaped(llvm::StringRef(ArMemHdr->LastModified,
+                                   sizeof(ArMemHdr->LastModified)).rtrim(" "));
+    OS.flush();
+    uint64_t Offset = reinterpret_cast<const char *>(ArMemHdr) -
+                      Parent->getData().data();
+    return malformedError("characters in LastModified field in archive header "
+                          "are not all decimal numbers: '" + Buf + "' for the "
+                          "archive member header at offset " + Twine(Offset));
+  }
 
-  sys::TimeValue Ret;
-  Ret.fromEpochTime(Seconds);
-  return Ret;
+  return sys::toTimePoint(Seconds);
 }
 
-unsigned ArchiveMemberHeader::getUID() const {
+Expected<unsigned> ArchiveMemberHeader::getUID() const {
   unsigned Ret;
-  StringRef User = StringRef(UID, sizeof(UID)).rtrim(' ');
+  StringRef User = StringRef(ArMemHdr->UID, sizeof(ArMemHdr->UID)).rtrim(' ');
   if (User.empty())
     return 0;
-  if (User.getAsInteger(10, Ret))
-    llvm_unreachable("UID time not a decimal number.");
+  if (User.getAsInteger(10, Ret)) {
+    std::string Buf;
+    raw_string_ostream OS(Buf);
+    OS.write_escaped(User);
+    OS.flush();
+    uint64_t Offset = reinterpret_cast<const char *>(ArMemHdr) -
+                      Parent->getData().data();
+    return malformedError("characters in UID field in archive header "
+                          "are not all decimal numbers: '" + Buf + "' for the "
+                          "archive member header at offset " + Twine(Offset));
+  }
   return Ret;
 }
 
-unsigned ArchiveMemberHeader::getGID() const {
+Expected<unsigned> ArchiveMemberHeader::getGID() const {
   unsigned Ret;
-  StringRef Group = StringRef(GID, sizeof(GID)).rtrim(' ');
+  StringRef Group = StringRef(ArMemHdr->GID, sizeof(ArMemHdr->GID)).rtrim(' ');
   if (Group.empty())
     return 0;
-  if (Group.getAsInteger(10, Ret))
-    llvm_unreachable("GID time not a decimal number.");
+  if (Group.getAsInteger(10, Ret)) {
+    std::string Buf;
+    raw_string_ostream OS(Buf);
+    OS.write_escaped(Group);
+    OS.flush();
+    uint64_t Offset = reinterpret_cast<const char *>(ArMemHdr) -
+                      Parent->getData().data();
+    return malformedError("characters in GID field in archive header "
+                          "are not all decimal numbers: '" + Buf + "' for the "
+                          "archive member header at offset " + Twine(Offset));
+  }
   return Ret;
 }
 
 Archive::Child::Child(const Archive *Parent, StringRef Data,
                       uint16_t StartOfFile)
-    : Parent(Parent), Data(Data), StartOfFile(StartOfFile) {}
+    : Parent(Parent), Header(Parent, Data.data(), Data.size(), nullptr),
+      Data(Data), StartOfFile(StartOfFile) {
+}
 
-Archive::Child::Child(const Archive *Parent, const char *Start,
-                      std::error_code *EC)
-    : Parent(Parent) {
+Archive::Child::Child(const Archive *Parent, const char *Start, Error *Err)
+    : Parent(Parent),
+      Header(Parent, Start,
+             Parent
+               ? Parent->getData().size() - (Start - Parent->getData().data())
+               : 0, Err) {
   if (!Start)
     return;
 
-  uint64_t Size = sizeof(ArchiveMemberHeader);
+  // If we are pointed to real data, Start is not a nullptr, then there must be
+  // a non-null Err pointer available to report malformed data on.  Only in
+  // the case sentinel value is being constructed is Err is permitted to be a
+  // nullptr.
+  assert(Err && "Err can't be nullptr if Start is not a nullptr");
+
+  ErrorAsOutParameter ErrAsOutParam(Err);
+
+  // If there was an error in the construction of the Header 
+  // then just return with the error now set.
+  if (*Err)
+    return;
+
+  uint64_t Size = Header.getSizeOf();
   Data = StringRef(Start, Size);
-  if (!isThinMember()) {
-    ErrorOr<uint64_t> MemberSize = getRawSize();
-    if ((*EC = MemberSize.getError()))
+  Expected<bool> isThinOrErr = isThinMember();
+  if (!isThinOrErr) {
+    *Err = isThinOrErr.takeError();
+    return;
+  }
+  bool isThin = isThinOrErr.get();
+  if (!isThin) {
+    Expected<uint64_t> MemberSize = getRawSize();
+    if (!MemberSize) {
+      *Err = MemberSize.takeError();
       return;
+    }
     Size += MemberSize.get();
     Data = StringRef(Start, Size);
   }
 
   // Setup StartOfFile and PaddingBytes.
-  StartOfFile = sizeof(ArchiveMemberHeader);
+  StartOfFile = Header.getSizeOf();
   // Don't include attached name.
-  StringRef Name = getRawName();
+  Expected<StringRef> NameOrErr = getRawName();
+  if (!NameOrErr){
+    *Err = NameOrErr.takeError();
+    return;
+  }
+  StringRef Name = NameOrErr.get();
   if (Name.startswith("#1/")) {
     uint64_t NameSize;
-    if (Name.substr(3).rtrim(' ').getAsInteger(10, NameSize))
-      llvm_unreachable("Long name length is not an integer");
+    if (Name.substr(3).rtrim(' ').getAsInteger(10, NameSize)) {
+      std::string Buf;
+      raw_string_ostream OS(Buf);
+      OS.write_escaped(Name.substr(3).rtrim(' '));
+      OS.flush();
+      uint64_t Offset = Start - Parent->getData().data();
+      *Err = malformedError("long name length characters after the #1/ are "
+                            "not all decimal numbers: '" + Buf + "' for "
+                            "archive member header at offset " +
+                            Twine(Offset));
+      return;
+    }
     StartOfFile += NameSize;
   }
 }
 
-ErrorOr<uint64_t> Archive::Child::getSize() const {
+Expected<uint64_t> Archive::Child::getSize() const {
   if (Parent->IsThin) {
-    ErrorOr<uint32_t> Size = getHeader()->getSize();
-    if (std::error_code EC = Size.getError())
-      return EC;
+    Expected<uint32_t> Size = Header.getSize();
+    if (!Size)
+      return Size.takeError();
     return Size.get();
   }
   return Data.size() - StartOfFile;
 }
 
-ErrorOr<uint64_t> Archive::Child::getRawSize() const {
-  ErrorOr<uint32_t> Size = getHeader()->getSize();
-  if (std::error_code EC = Size.getError())
-    return EC;
-  return Size.get();
+Expected<uint64_t> Archive::Child::getRawSize() const {
+  return Header.getSize();
 }
 
-bool Archive::Child::isThinMember() const {
-  StringRef Name = getHeader()->getName();
+Expected<bool> Archive::Child::isThinMember() const {
+  Expected<StringRef> NameOrErr = Header.getRawName();
+  if (!NameOrErr)
+    return NameOrErr.takeError();
+  StringRef Name = NameOrErr.get();
   return Parent->IsThin && Name != "/" && Name != "//";
 }
 
-ErrorOr<std::string> Archive::Child::getFullName() const {
-  assert(isThinMember());
-  ErrorOr<StringRef> NameOrErr = getName();
-  if (std::error_code EC = NameOrErr.getError())
-    return EC;
+Expected<std::string> Archive::Child::getFullName() const {
+  Expected<bool> isThin = isThinMember();
+  if (!isThin)
+    return isThin.takeError();
+  assert(isThin.get());
+  Expected<StringRef> NameOrErr = getName();
+  if (!NameOrErr)
+    return NameOrErr.takeError();
   StringRef Name = *NameOrErr;
   if (sys::path::is_absolute(Name))
     return Name;
@@ -156,25 +411,29 @@ ErrorOr<std::string> Archive::Child::getFullName() const {
   return StringRef(FullName);
 }
 
-ErrorOr<StringRef> Archive::Child::getBuffer() const {
-  if (!isThinMember()) {
-    ErrorOr<uint32_t> Size = getSize();
-    if (std::error_code EC = Size.getError())
-      return EC;
+Expected<StringRef> Archive::Child::getBuffer() const {
+  Expected<bool> isThinOrErr = isThinMember();
+  if (!isThinOrErr)
+    return isThinOrErr.takeError();
+  bool isThin = isThinOrErr.get();
+  if (!isThin) {
+    Expected<uint32_t> Size = getSize();
+    if (!Size)
+      return Size.takeError();
     return StringRef(Data.data() + StartOfFile, Size.get());
   }
-  ErrorOr<std::string> FullNameOrEr = getFullName();
-  if (std::error_code EC = FullNameOrEr.getError())
-    return EC;
-  const std::string &FullName = *FullNameOrEr;
+  Expected<std::string> FullNameOrErr = getFullName();
+  if (!FullNameOrErr)
+    return FullNameOrErr.takeError();
+  const std::string &FullName = *FullNameOrErr;
   ErrorOr<std::unique_ptr<MemoryBuffer>> Buf = MemoryBuffer::getFile(FullName);
   if (std::error_code EC = Buf.getError())
-    return EC;
+    return errorCodeToError(EC);
   Parent->ThinBuffers.push_back(std::move(*Buf));
   return Parent->ThinBuffers.back()->getBuffer();
 }
 
-ErrorOr<Archive::Child> Archive::Child::getNext() const {
+Expected<Archive::Child> Archive::Child::getNext() const {
   size_t SpaceToSkip = Data.size();
   // If it's odd, add 1 to make it even.
   if (SpaceToSkip & 1)
@@ -184,16 +443,25 @@ ErrorOr<Archive::Child> Archive::Child::getNext() const {
 
   // Check to see if this is at the end of the archive.
   if (NextLoc == Parent->Data.getBufferEnd())
-    return Child(Parent, nullptr, nullptr);
+    return Child(nullptr, nullptr, nullptr);
 
   // Check to see if this is past the end of the archive.
-  if (NextLoc > Parent->Data.getBufferEnd())
-    return object_error::parse_failed;
+  if (NextLoc > Parent->Data.getBufferEnd()) {
+    std::string Msg("offset to next archive member past the end of the archive "
+                    "after member ");
+    Expected<StringRef> NameOrErr = getName();
+    if (!NameOrErr) {
+      consumeError(NameOrErr.takeError());
+      uint64_t Offset = Data.data() - Parent->getData().data();
+      return malformedError(Msg + "at offset " + Twine(Offset));
+    } else
+      return malformedError(Msg + NameOrErr.get());
+  }
 
-  std::error_code EC;
-  Child Ret(Parent, NextLoc, &EC);
-  if (EC)
-    return EC;
+  Error Err = Error::success();
+  Child Ret(Parent, NextLoc, &Err);
+  if (Err)
+    return std::move(Err);
   return Ret;
 }
 
@@ -204,64 +472,34 @@ uint64_t Archive::Child::getChildOffset() const {
   return offset;
 }
 
-ErrorOr<StringRef> Archive::Child::getName() const {
-  StringRef name = getRawName();
-  // Check if it's a special name.
-  if (name[0] == '/') {
-    if (name.size() == 1) // Linker member.
-      return name;
-    if (name.size() == 2 && name[1] == '/') // String table.
-      return name;
-    // It's a long name.
-    // Get the offset.
-    std::size_t offset;
-    if (name.substr(1).rtrim(' ').getAsInteger(10, offset))
-      llvm_unreachable("Long name offset is not an integer");
-
-    // Verify it.
-    if (offset >= Parent->StringTable.size())
-      return object_error::parse_failed;
-    const char *addr = Parent->StringTable.begin() + offset;
-
-    // GNU long file names end with a "/\n".
-    if (Parent->kind() == K_GNU || Parent->kind() == K_MIPS64) {
-      StringRef::size_type End = StringRef(addr).find('\n');
-      return StringRef(addr, End - 1);
-    }
-    return StringRef(addr);
-  } else if (name.startswith("#1/")) {
-    uint64_t name_size;
-    if (name.substr(3).rtrim(' ').getAsInteger(10, name_size))
-      llvm_unreachable("Long name length is not an ingeter");
-    return Data.substr(sizeof(ArchiveMemberHeader), name_size).rtrim('\0');
-  } else {
-    // It is not a long name so trim the blanks at the end of the name.
-    if (name[name.size() - 1] != '/') {
-      return name.rtrim(' ');
-    }
-  }
-  // It's a simple name.
-  if (name[name.size() - 1] == '/')
-    return name.substr(0, name.size() - 1);
-  return name;
+Expected<StringRef> Archive::Child::getName() const {
+  Expected<uint64_t> RawSizeOrErr = getRawSize();
+  if (!RawSizeOrErr)
+    return RawSizeOrErr.takeError();
+  uint64_t RawSize = RawSizeOrErr.get();
+  Expected<StringRef> NameOrErr = Header.getName(Header.getSizeOf() + RawSize);
+  if (!NameOrErr)
+    return NameOrErr.takeError();
+  StringRef Name = NameOrErr.get();
+  return Name;
 }
 
-ErrorOr<MemoryBufferRef> Archive::Child::getMemoryBufferRef() const {
-  ErrorOr<StringRef> NameOrErr = getName();
-  if (std::error_code EC = NameOrErr.getError())
-    return EC;
+Expected<MemoryBufferRef> Archive::Child::getMemoryBufferRef() const {
+  Expected<StringRef> NameOrErr = getName();
+  if (!NameOrErr)
+    return NameOrErr.takeError();
   StringRef Name = NameOrErr.get();
-  ErrorOr<StringRef> Buf = getBuffer();
-  if (std::error_code EC = Buf.getError())
-    return EC;
+  Expected<StringRef> Buf = getBuffer();
+  if (!Buf)
+    return Buf.takeError();
   return MemoryBufferRef(*Buf, Name);
 }
 
 Expected<std::unique_ptr<Binary>>
 Archive::Child::getAsBinary(LLVMContext *Context) const {
-  ErrorOr<MemoryBufferRef> BuffOrErr = getMemoryBufferRef();
-  if (std::error_code EC = BuffOrErr.getError())
-    return errorCodeToError(EC);
+  Expected<MemoryBufferRef> BuffOrErr = getMemoryBufferRef();
+  if (!BuffOrErr)
+    return BuffOrErr.takeError();
 
   auto BinaryOrErr = createBinary(BuffOrErr.get(), Context);
   if (BinaryOrErr)
@@ -270,7 +508,7 @@ Archive::Child::getAsBinary(LLVMContext *Context) const {
 }
 
 Expected<std::unique_ptr<Archive>> Archive::create(MemoryBufferRef Source) {
-  Error Err;
+  Error Err = Error::success();
   std::unique_ptr<Archive> Ret(new Archive(Source, Err));
   if (Err)
     return std::move(Err);
@@ -284,7 +522,7 @@ void Archive::setFirstRegular(const Child &C) {
 
 Archive::Archive(MemoryBufferRef Source, Error &Err)
     : Binary(Binary::ID_Archive, Source) {
-  ErrorAsOutParameter ErrAsOutParam(Err);
+  ErrorAsOutParameter ErrAsOutParam(&Err);
   StringRef Buffer = Data.getBuffer();
   // Check for sufficient magic.
   if (Buffer.startswith(ThinMagic)) {
@@ -297,17 +535,20 @@ Archive::Archive(MemoryBufferRef Source, Error &Err)
     return;
   }
 
+  // Make sure Format is initialized before any call to
+  // ArchiveMemberHeader::getName() is made.  This could be a valid empty
+  // archive which is the same in all formats.  So claiming it to be gnu to is
+  // fine if not totally correct before we look for a string table or table of
+  // contents.
+  Format = K_GNU;
+
   // Get the special members.
   child_iterator I = child_begin(Err, false);
   if (Err)
     return;
   child_iterator E = child_end();
 
-  // This is at least a valid empty archive. Since an empty archive is the
-  // same in all formats, just claim it to be gnu to make sure Format is
-  // initialized.
-  Format = K_GNU;
-
+  // See if this is a valid empty archive and if so return.
   if (I == E) {
     Err = Error::success();
     return;
@@ -322,7 +563,12 @@ Archive::Archive(MemoryBufferRef Source, Error &Err)
     return false;
   };
 
-  StringRef Name = C->getRawName();
+  Expected<StringRef> NameOrErr = C->getRawName();
+  if (!NameOrErr) {
+    Err = NameOrErr.takeError();
+    return;
+  }
+  StringRef Name = NameOrErr.get();
 
   // Below is the pattern that is used to figure out the archive format
   // GNU archive format
@@ -348,9 +594,14 @@ Archive::Archive(MemoryBufferRef Source, Error &Err)
       Format = K_BSD;
     else // Name == "__.SYMDEF_64"
       Format = K_DARWIN64;
-    // We know that the symbol table is not an external file, so we just assert
-    // there is no error.
-    SymbolTable = *C->getBuffer();
+    // We know that the symbol table is not an external file, but we still must
+    // check any Expected<> return value.
+    Expected<StringRef> BufOrErr = C->getBuffer();
+    if (!BufOrErr) {
+      Err = BufOrErr.takeError();
+      return;
+    }
+    SymbolTable = BufOrErr.get();
     if (Increment())
       return;
     setFirstRegular(*C);
@@ -362,24 +613,34 @@ Archive::Archive(MemoryBufferRef Source, Error &Err)
   if (Name.startswith("#1/")) {
     Format = K_BSD;
     // We know this is BSD, so getName will work since there is no string table.
-    ErrorOr<StringRef> NameOrErr = C->getName();
-    if (auto ec = NameOrErr.getError()) {
-      Err = errorCodeToError(ec);
+    Expected<StringRef> NameOrErr = C->getName();
+    if (!NameOrErr) {
+      Err = NameOrErr.takeError();
       return;
     }
     Name = NameOrErr.get();
     if (Name == "__.SYMDEF SORTED" || Name == "__.SYMDEF") {
-      // We know that the symbol table is not an external file, so we just
-      // assert there is no error.
-      SymbolTable = *C->getBuffer();
+      // We know that the symbol table is not an external file, but we still
+      // must check any Expected<> return value.
+      Expected<StringRef> BufOrErr = C->getBuffer();
+      if (!BufOrErr) {
+        Err = BufOrErr.takeError();
+        return;
+      }
+      SymbolTable = BufOrErr.get();
       if (Increment())
         return;
     }
     else if (Name == "__.SYMDEF_64 SORTED" || Name == "__.SYMDEF_64") {
       Format = K_DARWIN64;
-      // We know that the symbol table is not an external file, so we just
-      // assert there is no error.
-      SymbolTable = *C->getBuffer();
+      // We know that the symbol table is not an external file, but we still
+      // must check any Expected<> return value.
+      Expected<StringRef> BufOrErr = C->getBuffer();
+      if (!BufOrErr) {
+        Err = BufOrErr.takeError();
+        return;
+      }
+      SymbolTable = BufOrErr.get();
       if (Increment())
         return;
     }
@@ -394,9 +655,14 @@ Archive::Archive(MemoryBufferRef Source, Error &Err)
 
   bool has64SymTable = false;
   if (Name == "/" || Name == "/SYM64/") {
-    // We know that the symbol table is not an external file, so we just assert
-    // there is no error.
-    SymbolTable = *C->getBuffer();
+    // We know that the symbol table is not an external file, but we still
+    // must check any Expected<> return value.
+    Expected<StringRef> BufOrErr = C->getBuffer();
+    if (!BufOrErr) {
+      Err = BufOrErr.takeError();
+      return;
+    }
+    SymbolTable = BufOrErr.get();
     if (Name == "/SYM64/")
       has64SymTable = true;
 
@@ -406,14 +672,24 @@ Archive::Archive(MemoryBufferRef Source, Error &Err)
       Err = Error::success();
       return;
     }
-    Name = C->getRawName();
+    Expected<StringRef> NameOrErr = C->getRawName();
+    if (!NameOrErr) {
+      Err = NameOrErr.takeError();
+      return;
+    }
+    Name = NameOrErr.get();
   }
 
   if (Name == "//") {
     Format = has64SymTable ? K_MIPS64 : K_GNU;
-    // The string table is never an external member, so we just assert on the
-    // ErrorOr.
-    StringTable = *C->getBuffer();
+    // The string table is never an external member, but we still
+    // must check any Expected<> return value.
+    Expected<StringRef> BufOrErr = C->getBuffer();
+    if (!BufOrErr) {
+      Err = BufOrErr.takeError();
+      return;
+    }
+    StringTable = BufOrErr.get();
     if (Increment())
       return;
     setFirstRegular(*C);
@@ -434,9 +710,14 @@ Archive::Archive(MemoryBufferRef Source, Error &Err)
   }
 
   Format = K_COFF;
-  // We know that the symbol table is not an external file, so we just assert
-  // there is no error.
-  SymbolTable = *C->getBuffer();
+  // We know that the symbol table is not an external file, but we still
+  // must check any Expected<> return value.
+  Expected<StringRef> BufOrErr = C->getBuffer();
+  if (!BufOrErr) {
+    Err = BufOrErr.takeError();
+    return;
+  }
+  SymbolTable = BufOrErr.get();
 
   if (Increment())
     return;
@@ -447,12 +728,22 @@ Archive::Archive(MemoryBufferRef Source, Error &Err)
     return;
   }
 
-  Name = C->getRawName();
+  NameOrErr = C->getRawName();
+  if (!NameOrErr) {
+    Err = NameOrErr.takeError();
+    return;
+  }
+  Name = NameOrErr.get();
 
   if (Name == "//") {
-    // The string table is never an external member, so we just assert on the
-    // ErrorOr.
-    StringTable = *C->getBuffer();
+    // The string table is never an external member, but we still
+    // must check any Expected<> return value.
+    Expected<StringRef> BufOrErr = C->getBuffer();
+    if (!BufOrErr) {
+      Err = BufOrErr.takeError();
+      return;
+    }
+    StringTable = BufOrErr.get();
     if (Increment())
       return;
   }
@@ -463,7 +754,7 @@ Archive::Archive(MemoryBufferRef Source, Error &Err)
 
 Archive::child_iterator Archive::child_begin(Error &Err,
                                              bool SkipInternal) const {
-  if (Data.getBufferSize() == 8) // empty archive.
+  if (isEmpty())
     return child_end();
 
   if (SkipInternal)
@@ -472,25 +763,21 @@ Archive::child_iterator Archive::child_begin(Error &Err,
                           &Err);
 
   const char *Loc = Data.getBufferStart() + strlen(Magic);
-  std::error_code EC;
-  Child C(this, Loc, &EC);
-  if (EC) {
-    ErrorAsOutParameter ErrAsOutParam(Err);
-    Err = errorCodeToError(EC);
+  Child C(this, Loc, &Err);
+  if (Err)
     return child_end();
-  }
   return child_iterator(C, &Err);
 }
 
 Archive::child_iterator Archive::child_end() const {
-  return child_iterator(Child(this, nullptr, nullptr), nullptr);
+  return child_iterator(Child(nullptr, nullptr, nullptr), nullptr);
 }
 
 StringRef Archive::Symbol::getName() const {
   return Parent->getSymbolTable().begin() + StringIndex;
 }
 
-ErrorOr<Archive::Child> Archive::Symbol::getMember() const {
+Expected<Archive::Child> Archive::Symbol::getMember() const {
   const char *Buf = Parent->getSymbolTable().begin();
   const char *Offsets = Buf;
   if (Parent->kind() == K_MIPS64 || Parent->kind() == K_DARWIN64)
@@ -525,7 +812,7 @@ ErrorOr<Archive::Child> Archive::Symbol::getMember() const {
 
     uint32_t SymbolCount = read32le(Buf);
     if (SymbolIndex >= SymbolCount)
-      return object_error::parse_failed;
+      return errorCodeToError(object_error::parse_failed);
 
     // Skip SymbolCount to get to the indices table.
     const char *Indices = Buf + 4;
@@ -537,16 +824,16 @@ ErrorOr<Archive::Child> Archive::Symbol::getMember() const {
     --OffsetIndex;
 
     if (OffsetIndex >= MemberCount)
-      return object_error::parse_failed;
+      return errorCodeToError(object_error::parse_failed);
 
     Offset = read32le(Offsets + OffsetIndex * 4);
   }
 
   const char *Loc = Parent->getData().begin() + Offset;
-  std::error_code EC;
-  Child C(Parent, Loc, &EC);
-  if (EC)
-    return EC;
+  Error Err = Error::success();
+  Child C(Parent, Loc, &Err);
+  if (Err)
+    return std::move(Err);
   return C;
 }
 
@@ -677,10 +964,13 @@ Expected<Optional<Archive::Child>> Archive::findSym(StringRef name) const {
       if (auto MemberOrErr = bs->getMember())
         return Child(*MemberOrErr);
       else
-        return errorCodeToError(MemberOrErr.getError());
+        return MemberOrErr.takeError();
     }
   }
   return Optional<Child>();
 }
 
+// Returns true if archive file contains no member file.
+bool Archive::isEmpty() const { return Data.getBufferSize() == 8; }
+
 bool Archive::hasSymbolTable() const { return !SymbolTable.empty(); }