fix PR6814 - Only print [-pedantic] on a diagnostic if -pedantic

actually turned it on.  If a diag is produced by a warning which
is an extension but defaults to on, and has no warning group, don't
print any option info.

llvm-svn: 101071

1 files changed, 7 insertions, 2 deletions

diff --git a/clang/lib/Frontend/TextDiagnosticPrinter.cpp b/clang/lib/Frontend/TextDiagnosticPrinter.cpp
index 4e91f8d4c22..6c8137e3d29 100644
--- a/clang/lib/Frontend/TextDiagnosticPrinter.cpp
+++ b/clang/lib/Frontend/TextDiagnosticPrinter.cpp
@@ -796,8 +796,13 @@ void TextDiagnosticPrinter::HandleDiagnostic(Diagnostic::Level Level,
       OutStr += " [-W";
       OutStr += Opt;
       OutStr += ']';
-    } else if (Diagnostic::isBuiltinExtensionDiag(Info.getID())) {
-      OutStr += " [-pedantic]";
+    } else {
+      // If the diagnostic is an extension diagnostic and not enabled by default
+      // then it must have been turned on with -pedantic.
+      bool EnabledByDefault;
+      if (Diagnostic::isBuiltinExtensionDiag(Info.getID(), EnabledByDefault) &&
+          !EnabledByDefault)
+        OutStr += " [-pedantic]";
     }
   }