Handle and warn on aliases to weak aliases.

This produces valid IR now that llvm rejects aliases to weak aliases and warns
the user that the resolution is not changed if the weak alias is overridden.

llvm-svn: 204935

1 files changed, 6 insertions, 0 deletions

diff --git a/clang/test/CodeGen/alias.c b/clang/test/CodeGen/alias.c
index efa94b340bb..4a89b13be95 100644
--- a/clang/test/CodeGen/alias.c
+++ b/clang/test/CodeGen/alias.c
@@ -14,6 +14,8 @@ void f0(void) { }
 extern void f1(void);
 extern void f1(void) __attribute((alias("f0")));
 // CHECKBASIC-DAG: @f1 = alias void ()* @f0
+// CHECKBASIC-DAG: @test8_foo = alias weak bitcast (void ()* @test8_bar to void (...)*)
+// CHECKBASIC-DAG: @test8_zed = alias bitcast (void ()* @test8_bar to void (...)*)
 // CHECKBASIC: define void @f0() [[NUW:#[0-9]+]] {
 
 // Make sure that aliases cause referenced values to be emitted.
@@ -48,3 +50,7 @@ int outer_weak(int a) { return inner_weak_a(a); }
 // CHECKBASIC: attributes [[NUW]] = { nounwind{{.*}} }
 
 // CHECKCC: attributes [[NUW]] = { nounwind{{.*}} }
+
+void test8_bar() {}
+void test8_foo() __attribute__((weak, alias("test8_bar")));
+void test8_zed() __attribute__((alias("test8_foo")));