From 9db62af77a0fe049a533f53a92bf1c9e2d267050 Mon Sep 17 00:00:00 2001
From: David Blaikie <dblaikie@gmail.com>
Date: Tue, 4 Mar 2014 03:08:14 +0000
Subject: [PATCH] DebugInfo: Improvements/corrections to conservative emission
 of types in explicit template instantiation declarations

* detect out of line definitions correctly
* detect member function explicit specializations correctly

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@202779 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/CGDebugInfo.cpp                   |  3 ++-
 ...-info-template-explicit-specialization.cpp | 20 +++++++++++++------
 2 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index 6c24e8f865..35bd57a053 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -1462,7 +1462,8 @@ static bool hasExplicitMemberDefinition(CXXRecordDecl::method_iterator I,
                                         CXXRecordDecl::method_iterator End) {
   for (; I != End; ++I)
     if (FunctionDecl *Tmpl = I->getInstantiatedFromMemberFunction())
-      if (!Tmpl->isImplicit() && Tmpl->hasBody())
+      if (!Tmpl->isImplicit() && Tmpl->isThisDeclarationADefinition() &&
+          !I->getMemberSpecializationInfo()->isExplicitSpecialization())
         return true;
   return false;
 }
diff --git a/test/CodeGenCXX/debug-info-template-explicit-specialization.cpp b/test/CodeGenCXX/debug-info-template-explicit-specialization.cpp
index 6dfffb6114..86380392a2 100644
--- a/test/CodeGenCXX/debug-info-template-explicit-specialization.cpp
+++ b/test/CodeGenCXX/debug-info-template-explicit-specialization.cpp
@@ -38,7 +38,10 @@ void e<T>::f() {
 }
 extern template class e<int>;
 e<int> ei;
-// CHECK: ; [ DW_TAG_structure_type ] [e<int>] {{.*}} [decl]
+// There's no guarantee that the out of line definition will appear before the
+// explicit template instantiation definition, so conservatively emit the type
+// definition here.
+// CHECK: ; [ DW_TAG_structure_type ] [e<int>] {{.*}} [def]
 
 template <typename T>
 struct f {
@@ -49,11 +52,7 @@ template <typename T>
 void f<T>::g() {
 }
 f<int> fi;
-// Is this right? We don't seem to emit a def for 'f<int>::g' (even if it is
-// called in this translation unit) so I guess if we're relying on its
-// definition to be wherever the explicit instantiation definition is, we can do
-// the same for the debug info.
-// CHECK: ; [ DW_TAG_structure_type ] [f<int>] {{.*}} [decl]
+// CHECK: ; [ DW_TAG_structure_type ] [f<int>] {{.*}} [def]
 
 template <typename T>
 struct g {
@@ -70,3 +69,12 @@ struct h {
 };
 template class h<int>;
 // CHECK: ; [ DW_TAG_structure_type ] [h<int>] {{.*}} [def]
+
+template <typename T>
+struct i {
+  void f() {}
+};
+template<> void i<int>::f();
+extern template class i<int>;
+i<int> ii;
+// CHECK: ; [ DW_TAG_structure_type ] [i<int>] {{.*}} [def]
-- 
2.40.0