daniel remembered why this was needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96440 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86MCAsmInfo.cpp b/lib/Target/X86/X86MCAsmInfo.cpp
index b220cff..bc56e71 100644
--- a/lib/Target/X86/X86MCAsmInfo.cpp
+++ b/lib/Target/X86/X86MCAsmInfo.cpp
@@ -56,7 +56,10 @@
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.
+ // through the GCC preprocessor without causing an error. This is needed
+ // because "clang foo.s" runs the C preprocessor, which is usually reserved
+ // for .S files on other systems. Perhaps this is because the file system
+ // wasn't always case preserving or something.
CommentString = "##";
PCSymbol = ".";