[Sema] Fix -Wcomma for C89

There is a small difference in the scope flags for C89 versus the other C/C++
dialects.  This change ensures that the -Wcomma warning won't be duplicated or
issued in the wrong location.  Also, the test case is refactored into C and C++
parts, with the C++ parts guarded by a #ifdef to allow the test to run in both
modes.

https://bugs.llvm.org/show_bug.cgi?id=32370

llvm-svn: 345228

1 files changed, 8 insertions, 2 deletions

diff --git a/clang/lib/Sema/SemaStmt.cpp b/clang/lib/Sema/SemaStmt.cpp
index 16ed9ed767c..7fc89bfd69a 100644
--- a/clang/lib/Sema/SemaStmt.cpp
+++ b/clang/lib/Sema/SemaStmt.cpp
@@ -551,8 +551,9 @@ Sema::ActOnIfStmt(SourceLocation IfLoc, bool IsConstexpr, Stmt *InitStmt,
         false);
 
   Expr *CondExpr = Cond.get().second;
-  if (!Diags.isIgnored(diag::warn_comma_operator,
-                       CondExpr->getExprLoc()))
+  // Only call the CommaVisitor when not C89 due to differences in scope flags.
+  if ((getLangOpts().C99 || getLangOpts().CPlusPlus) &&
+      !Diags.isIgnored(diag::warn_comma_operator, CondExpr->getExprLoc()))
     CommaVisitor(*this).Visit(CondExpr);
 
   if (!elseStmt)
@@ -1328,6 +1329,11 @@ Sema::ActOnDoStmt(SourceLocation DoLoc, Stmt *Body,
     return StmtError();
   Cond = CondResult.get();
 
+  // Only call the CommaVisitor for C89 due to differences in scope flags.
+  if (Cond && !getLangOpts().C99 && !getLangOpts().CPlusPlus &&
+      !Diags.isIgnored(diag::warn_comma_operator, Cond->getExprLoc()))
+    CommaVisitor(*this).Visit(Cond);
+
   DiagnoseUnusedExprResult(Body);
 
   return new (Context) DoStmt(Body, Cond, DoLoc, WhileLoc, CondRParen);