Teach printf/scanf about enums with fixed underlying types.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@157961 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Sema/format-strings-enum.c b/test/Sema/format-strings-enum.c
new file mode 100644
index 0000000..a6c27d0
--- /dev/null
+++ b/test/Sema/format-strings-enum.c
@@ -0,0 +1,36 @@
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -verify %s
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -x c++ -verify %s
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -x c++ -std=c++11 -verify %s
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -x objective-c -verify %s
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -x objective-c++ -std=c++11 -verify %s
+
+#ifdef __cplusplus
+# define EXTERN_C extern "C"
+#else
+# define EXTERN_C extern
+#endif
+
+EXTERN_C int printf(const char *,...);
+
+typedef enum { Constant = 0 } TestEnum;
+// Note that in C, the type of 'Constant' is 'int'. In C++ it is 'TestEnum'.
+// This is why we don't check for that in the expected output.
+
+void test(TestEnum input) {
+    printf("%d", input); // no-warning
+    printf("%d", Constant); // no-warning
+
+    printf("%lld", input); // expected-warning{{format specifies type 'long long' but the argument has type 'TestEnum'}}
+    printf("%lld", Constant); // expected-warning{{format specifies type 'long long'}}
+}
+
+
+typedef enum { LongConstant = ~0UL } LongEnum;
+
+void testLong(LongEnum input) {
+  printf("%u", input); // expected-warning{{format specifies type 'unsigned int' but the argument has type 'LongEnum'}}
+  printf("%u", LongConstant); // expected-warning{{format specifies type 'unsigned int'}}
+  
+  printf("%lu", input);
+  printf("%lu", LongConstant);
+}