Add an opt-in -Wheader-hygiene, which current diagnoses the use of

global using directives in C++ headers, from Elliot Glaysher!


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@127881 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 9 insertions, 0 deletions

diff --git a/test/SemaCXX/warn-using-namespace-in-header.cpp b/test/SemaCXX/warn-using-namespace-in-header.cpp
new file mode 100644
index 0000000000..393e097df5
--- /dev/null
+++ b/test/SemaCXX/warn-using-namespace-in-header.cpp
@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -fsyntax-only -Wheader-hygiene -verify %s
+
+#include "warn-using-namespace-in-header.h"
+
+namespace dont_warn {}
+using namespace dont_warn;
+
+// Warning is actually in the header but only the cpp file gets scanned.
+// expected-warning {{using namespace directive in global context in header}}