squash warnings.

llvm-svn: 61707
diff --git a/llvm/lib/Target/X86/X86TargetAsmInfo.cpp b/llvm/lib/Target/X86/X86TargetAsmInfo.cpp
index de655e7..1cf859b 100644
--- a/llvm/lib/Target/X86/X86TargetAsmInfo.cpp
+++ b/llvm/lib/Target/X86/X86TargetAsmInfo.cpp
@@ -319,6 +319,7 @@
    default:
     assert(0 && "Unknown section kind");
   }
+  return NULL;
 }
 
 std::string X86COFFTargetAsmInfo::printSectionFlags(unsigned flags) const {