Hook up 'invalid conversion' warning for scanf format strings.

llvm-svn: 108750
diff --git a/clang/test/Sema/format-strings-scanf.c b/clang/test/Sema/format-strings-scanf.c
index ac53d66..5d2a7a7 100644
--- a/clang/test/Sema/format-strings-scanf.c
+++ b/clang/test/Sema/format-strings-scanf.c
@@ -15,4 +15,5 @@
 
   unsigned short s_x;
   scanf ("%" "hu" "\n", &s_x); // no-warning
+  scanf("%y", i); // expected-warning{{invalid conversion specifier 'y'}}
 }