From 279cb3d7c63ab4613f11dfe008af1882d196571e Mon Sep 17 00:00:00 2001
From: Adrian Prantl <aprantl@apple.com>
Date: Thu, 17 Apr 2014 00:30:48 +0000
Subject: [PATCH] Debug info: When collecting the parameters of C++ partial
 template specializations collect all arguments and not just the ones from the
 class template partial specialization from which this class template
 specialization was instantiated. The debug info does not represent the
 partial specialization otherwise and so specialized parameters would go
 missing.

rdar://problem/16636569.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@206430 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/CGDebugInfo.cpp                   | 14 ++++++---
 ...g-info-template-partial-specialization.cpp | 31 +++++++++++++++++++
 2 files changed, 41 insertions(+), 4 deletions(-)
 create mode 100644 test/CodeGenCXX/debug-info-template-partial-specialization.cpp

diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index 8e06bbd34b..dc49e1865e 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -1360,10 +1360,16 @@ CollectCXXTemplateParams(const ClassTemplateSpecializationDecl *TSpecial,
                      ClassTemplatePartialSpecializationDecl *>
     PU = TSpecial->getSpecializedTemplateOrPartial();
 
-  TemplateParameterList *TPList = PU.is<ClassTemplateDecl *>() ?
-    PU.get<ClassTemplateDecl *>()->getTemplateParameters() :
-    PU.get<ClassTemplatePartialSpecializationDecl *>()->getTemplateParameters();
-  const TemplateArgumentList &TAList = TSpecial->getTemplateInstantiationArgs();
+  TemplateParameterList *TPList;
+  if (auto *CTD = PU.dyn_cast<ClassTemplateDecl *>())
+    TPList = CTD->getTemplateParameters();
+  else {
+    // Always get the full list of parameters, not just the ones from
+    // the specialization.
+    auto *CTPSD = PU.get<ClassTemplatePartialSpecializationDecl *>();
+    TPList = CTPSD->getSpecializedTemplate()->getTemplateParameters();
+  }
+  const TemplateArgumentList &TAList = TSpecial->getTemplateArgs();
   return CollectTemplateParams(TPList, TAList.asArray(), Unit);
 }
 
diff --git a/test/CodeGenCXX/debug-info-template-partial-specialization.cpp b/test/CodeGenCXX/debug-info-template-partial-specialization.cpp
new file mode 100644
index 0000000000..cce84af402
--- /dev/null
+++ b/test/CodeGenCXX/debug-info-template-partial-specialization.cpp
@@ -0,0 +1,31 @@
+// RUN: %clang_cc1 -emit-llvm -triple %itanium_abi_triple -g %s -o - -fstandalone-debug | FileCheck %s
+namespace __pointer_type_imp
+{
+  template <class _Tp, class _Dp, bool > struct __pointer_type1 {};
+
+  // CHECK: metadata ![[PARAMS:[0-9]+]], metadata !"_ZTSN18__pointer_type_imp15__pointer_type1I1C14default_deleteIS1_ELb0EEE"} ; [ DW_TAG_structure_type ] [__pointer_type1<C, default_delete<C>, false>] [line [[@LINE+1]], size 8, align 8, offset 0] [def] [from ]
+  template <class _Tp, class _Dp> struct __pointer_type1<_Tp, _Dp, false>
+  {
+    typedef _Tp* type;
+  };
+}
+template <class _Tp, class _Dp>
+struct __pointer_type2
+{
+  // Test that the bool template type parameter is emitted.
+  //
+  // CHECK: ![[PARAMS]] = metadata !{metadata !{{.*}}, metadata !{{.*}}, metadata ![[FALSE:[0-9]+]]}
+  // CHECK: ![[FALSE]] = {{.*}} i8 0, {{.*}}} ; [ DW_TAG_template_value_parameter ]
+  typedef typename __pointer_type_imp::__pointer_type1<_Tp, _Dp, false>::type type;
+};
+template <class _Tp> struct default_delete {};
+template <class _Tp, class _Dp = default_delete<_Tp> > class unique_ptr
+{
+  typedef typename __pointer_type2<_Tp, _Dp>::type pointer;
+  unique_ptr(pointer __p, _Dp __d) {}
+};
+class C {
+  unique_ptr<C> Ptr;
+};
+void foo(C &c) {
+}
-- 
2.40.0