Don't warn about null characters in Objective-C format string literals.

llvm-svn: 127703

clang/lib/Sema/SemaChecking.cpp

@@ -1218,10 +1218,12 @@ void CheckFormatHandler::HandleZeroPosition(const char *startPos,
 }
 
 void CheckFormatHandler::HandleNullChar(const char *nullCharacter) {
-  // The presence of a null character is likely an error.
-  S.Diag(getLocationOfByte(nullCharacter),
-         diag::warn_printf_format_string_contains_null_char)
-    << getFormatStringRange();
+  if (!IsObjCLiteral) {
+    // The presence of a null character is likely an error.
+    S.Diag(getLocationOfByte(nullCharacter),
+           diag::warn_printf_format_string_contains_null_char)
+      << getFormatStringRange();
+  }
 }
 
 const Expr *CheckFormatHandler::getDataArg(unsigned i) const {