new testcase for the GNU comma swallow extension.

llvm-svn: 38779

1 files changed, 16 insertions, 0 deletions

diff --git a/clang/test/Preprocessor/macro_fn_comma_swallow.c b/clang/test/Preprocessor/macro_fn_comma_swallow.c
new file mode 100644
index 00000000000..d4f3bb9940d
--- /dev/null
+++ b/clang/test/Preprocessor/macro_fn_comma_swallow.c
@@ -0,0 +1,16 @@
+// Test the GNU comma swallowing extension.
+// RUN: clang %s -E | grep 'foo{A, }' && 
+// RUN: clang %s -E | grep 'fo2{A,}' && 
+// RUN: clang %s -E | grep '{foo}'
+
+#define X(Y) foo{A, Y}
+X()
+
+#define X2(Y) fo2{A,##Y}
+X2()
+
+// should eat the comma.
+#define X3(b, ...) {b, ## __VA_ARGS__}
+X3(foo)
+
+