Make __gnu_inline__ functions in gnu99 mode work the same way as inline functions in gnu89 mode in terms of redefinitions.
rdar://9559708 .
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@132953 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Sema/inline-redef.c b/test/Sema/inline-redef.c
new file mode 100644
index 0000000..4a46e11
--- /dev/null
+++ b/test/Sema/inline-redef.c
@@ -0,0 +1,24 @@
+// RUN: %clang_cc1 -std=gnu89 -fsyntax-only -verify %s
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+#if __STDC_VERSION__ >= 199901
+#define GNU_INLINE __attribute((__gnu_inline__))
+#else
+#define GNU_INLINE
+#endif
+
+// PR5253
+// rdar://9559708 (same extension in C99 mode)
+// GNU Extension: check that we can redefine an extern inline function
+GNU_INLINE extern inline int f(int a) {return a;}
+int f(int b) {return b;} // expected-note{{previous definition is here}}
+// And now check that we can't redefine a normal function
+int f(int c) {return c;} // expected-error{{redefinition of 'f'}}
+
+// Check that we can redefine an extern inline function as a static function
+GNU_INLINE extern inline int g(int a) {return a;}
+static int g(int b) {return b;}
+
+// Check that we ensure the types of the two definitions are the same
+GNU_INLINE extern inline int h(int a) {return a;} // expected-note{{previous definition is here}}
+int h(short b) {return b;} // expected-error{{conflicting types for 'h'}}