add a comment explaining why darwin/i386 uses ## as a comment.
It's not clear why this is really required, but it was explicitly
added in r48808 with no real explanation or rdar #.
llvm-svn: 96438
diff --git a/llvm/lib/Target/X86/X86MCAsmInfo.cpp b/llvm/lib/Target/X86/X86MCAsmInfo.cpp
index 6701fab..b220cff 100644
--- a/llvm/lib/Target/X86/X86MCAsmInfo.cpp
+++ b/llvm/lib/Target/X86/X86MCAsmInfo.cpp
@@ -55,6 +55,8 @@
if (!is64Bit)
Data64bitsDirective = 0; // we can't emit a 64-bit unit
+ // Use ## as a comment string so that .s files generated by llvm can go
+ // through the GCC preprocessor without causing an error.
CommentString = "##";
PCSymbol = ".";