Change our silencing of C typedef redefinition handling to what we had
before r69391: typedef redefinition is an error by default, but if
*either* the old or new definition are from a system header, we silence
it.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70177 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 1ea3a9e..482c304 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -560,7 +560,12 @@
// If we have a redefinition of a typedef in C, emit a warning. This warning
// is normally mapped to an error, but can be controlled with
- // -Wtypedef-redefinition.
+ // -Wtypedef-redefinition. If either the original was in a system header,
+ // don't emit this for compatibility with GCC.
+ if (PP.getDiagnostics().getSuppressSystemWarnings() &&
+ Context.getSourceManager().isInSystemHeader(Old->getLocation()))
+ return;
+
Diag(New->getLocation(), diag::warn_redefinition_of_typedef)
<< New->getDeclName();
Diag(Old->getLocation(), diag::note_previous_definition);