Add test case for fix of linkage bug that miscompiled variable templates instantiated from similarly named local types (cf. r212233)

lvoufo · lvoufo · commit 3f02d8af670e · 2014-07-25T23:58:13.000Z
llvm-svn: 213987
diff --git a/clang/test/CodeGenCXX/cxx1y-variable-template-linkage.cpp b/clang/test/CodeGenCXX/cxx1y-variable-template-linkage.cpp
@@ -0,0 +1,40 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-llvm -std=c++1y -O1 -disable-llvm-optzns %s -o - | FileCheck %s -check-prefix=CHECKA -check-prefix=CHECK
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-llvm -std=c++1y -O1 -disable-llvm-optzns -fcxx-exceptions %s -o - | FileCheck %s -check-prefix=CHECKB -check-prefix=CHECK
+// expected-no-diagnostics
+
+// The variable template specialization x<Foo> generated in each file
+// should be 'internal global' and not 'linkonce_odr global'.
+
+template <typename T> int x = 42;
+
+// CHECK-DAG: @_Z1xIZL3foovE3FooE = internal global
+
+// CHECK-DAG: define internal dereferenceable(4) i32* @_ZL3foov(
+static int &foo() {
+   struct Foo { };
+   
+   // CHECK-DAG: ret i32* @_Z1xIZL3foovE3FooE
+   return x<Foo>;
+}
+
+
+#if !__has_feature(cxx_exceptions) // File A
+// CHECKA-DAG: define dereferenceable(4) i32* @_Z3barv(
+int &bar() { 
+	// CHECKA-DAG: %call = call dereferenceable(4) i32* @_ZL3foov()
+	return foo();
+}
+
+#else // File B
+
+// CHECKB-DAG: declare dereferenceable(4) i32* @_Z3barv(
+int &bar();
+
+int main() {
+	// CHECKB-DAG: %call = call dereferenceable(4) i32* @_Z3barv()
+	// CHECKB-DAG: %call1 = call dereferenceable(4) i32* @_ZL3foov()
+	&bar() == &foo() ? throw 0 : (void)0; // Should not throw exception at runtime.
+}
+
+#endif // end of Files A and B
+
