PR12710 - broken default argument handling for templates.

I broke this in r155838 by not actually instantiating non-dependent default arg
expressions. The motivation for that change was to avoid producing duplicate
conversion warnings for such default args (we produce them once when we parse
the template - there's no need to produce them at each instantiation) but
without actually instantiating the default arg, things break in weird ways.

Technically, I think we could still get the right diagnostic experience without
the bugs if we instantiated the non-dependent args (for non-dependent params
only) immediately, rather than lazily. But I'm not sure if such a refactoring/
change would be desirable so here's the conservative fix for now.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@155893 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 16 insertions, 0 deletions

diff --git a/test/CodeGenCXX/destructors.cpp b/test/CodeGenCXX/destructors.cpp
index d9962e615e..b8ec2761be 100644
--- a/test/CodeGenCXX/destructors.cpp
+++ b/test/CodeGenCXX/destructors.cpp
@@ -350,6 +350,22 @@ namespace test8 {
   // CHECK:      unreachable
 }
 
+// PR12710
+namespace test9 {
+  struct ArgType {
+    ~ArgType();
+  };
+  template<typename T>
+  void f1(const ArgType& = ArgType());
+  void f2();
+  void bar() {
+    f1<int>();
+    f2();
+  }
+  // CHECK: call void @_ZN5test97ArgTypeD1Ev(%"struct.test9::ArgType"* %ref.tmp)
+  // CHECK: call void @_ZN5test92f2Ev()
+}
+
 // Checks from test3:
 
   // CHECK: define internal void @_ZN5test312_GLOBAL__N_11DD0Ev(%"struct.test3::<anonymous namespace>::D"* %this) unnamed_addr