1 files changed, 76 insertions, 0 deletions
diff --git a/contrib/llvm/patches/patch-r262611-llvm-r196874-fix-invalid-pwd-crash.diff b/contrib/llvm/patches/patch-r262611-llvm-r196874-fix-invalid-pwd-crash.diff
new file mode 100644
index 0000000..587693d
--- /dev/null
+++ b/contrib/llvm/patches/patch-r262611-llvm-r196874-fix-invalid-pwd-crash.diff
@@ -0,0 +1,76 @@
+Pull in r196874 from upstream llvm trunk (by Andrew Trick):
+
+  Fix a crash that occurs when PWD is invalid.
+
+  MCJIT needs to be able to run in hostile environments, even when PWD
+  is invalid. There's no need to crash MCJIT in this case.
+
+  The obvious fix is to simply leave MCContext's CompilationDir empty
+  when PWD can't be determined. This way, MCJIT clients,
+  and other clients that link with LLVM don?\226?\128?\153t need a valid working directory.
+
+  If we do want to guarantee valid CompilationDir, that should be done
+  only for clients of getCompilationDir(). This is as simple as checking
+  for an empty string.
+
+  The only current use of getCompilationDir is EmitGenDwarfInfo, which
+  won?\226?\128?\153t conceivably run with an invalid working dir. However, in the
+  purely hypothetically and untestable case that this happens, the
+  AT_comp_dir will be omitted from the compilation_unit DIE.
+
+Introduced here: http://svn.freebsd.org/changeset/base/262611
+
+Index: include/llvm/MC/MCContext.h
+===================================================================
+--- include/llvm/MC/MCContext.h
++++ include/llvm/MC/MCContext.h
+@@ -278,6 +278,7 @@ namespace llvm {
+     /// This can be overridden by clients which want to control the reported
+     /// compilation directory and have it be something other than the current
+     /// working directory.
++    /// Returns an empty string if the current directory cannot be determined.
+     StringRef getCompilationDir() const { return CompilationDir; }
+ 
+     /// \brief Set the compilation directory for DW_AT_comp_dir
+Index: lib/MC/MCContext.cpp
+===================================================================
+--- lib/MC/MCContext.cpp
++++ lib/MC/MCContext.cpp
+@@ -47,8 +47,8 @@ MCContext::MCContext(const MCAsmInfo *mai, const M
+   AllowTemporaryLabels(true), DwarfCompileUnitID(0), AutoReset(DoAutoReset) {
+ 
+   error_code EC = llvm::sys::fs::current_path(CompilationDir);
+-  assert(!EC && "Could not determine the current directory");
+-  (void)EC;
++  if (EC)
++    CompilationDir.clear();
+ 
+   MachOUniquingMap = 0;
+   ELFUniquingMap = 0;
+Index: lib/MC/MCDwarf.cpp
+===================================================================
+--- lib/MC/MCDwarf.cpp
++++ lib/MC/MCDwarf.cpp
+@@ -467,7 +467,8 @@ static void EmitGenDwarfAbbrev(MCStreamer *MCOS) {
+   EmitAbbrev(MCOS, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr);
+   EmitAbbrev(MCOS, dwarf::DW_AT_high_pc, dwarf::DW_FORM_addr);
+   EmitAbbrev(MCOS, dwarf::DW_AT_name, dwarf::DW_FORM_string);
+-  EmitAbbrev(MCOS, dwarf::DW_AT_comp_dir, dwarf::DW_FORM_string);
++  if (!context.getCompilationDir().empty())
++    EmitAbbrev(MCOS, dwarf::DW_AT_comp_dir, dwarf::DW_FORM_string);
+   StringRef DwarfDebugFlags = context.getDwarfDebugFlags();
+   if (!DwarfDebugFlags.empty())
+     EmitAbbrev(MCOS, dwarf::DW_AT_APPLE_flags, dwarf::DW_FORM_string);
+@@ -643,8 +644,10 @@ static void EmitGenDwarfInfo(MCStreamer *MCOS,
+   MCOS->EmitIntValue(0, 1); // NULL byte to terminate the string.
+ 
+   // AT_comp_dir, the working directory the assembly was done in.
+-  MCOS->EmitBytes(context.getCompilationDir());
+-  MCOS->EmitIntValue(0, 1); // NULL byte to terminate the string.
++  if (!context.getCompilationDir().empty()) {
++    MCOS->EmitBytes(context.getCompilationDir());
++    MCOS->EmitIntValue(0, 1); // NULL byte to terminate the string.
++  }
+ 
+   // AT_APPLE_flags, the command line arguments of the assembler tool.
+   StringRef DwarfDebugFlags = context.getDwarfDebugFlags();