This is not considered a preprocessor directive in .S files:

# 4

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@67233 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Lex/PPDirectives.cpp b/lib/Lex/PPDirectives.cpp
index 5a4d2ee15e38196de4e7c4e29ebac8532aef6b9e..8e76b920aab79c5bf79b61ec1876e96e84201900 100644 (file)
--- a/lib/Lex/PPDirectives.cpp
+++ b/lib/Lex/PPDirectives.cpp
@@ -499,6 +499,8 @@ TryAgain:
     goto TryAgain;
 
   case tok::numeric_constant:  // # 7  GNU line marker directive.
+    if (getLangOptions().AsmPreprocessor)
+      break;  // # 4 is not a preprocessor directive in .S files.
     return HandleDigitDirective(Result);
   default:
     IdentifierInfo *II = Result.getIdentifierInfo();