Fix deserializing of class template partial specializations. Assign sequence
numbers as we deserialize class template partial specializations. We can't
assume that the old sequence numbers will work.

The sequence numbers are still deterministic, but are now a lot less
predictable for class template partial specializations in modules/PCH.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@184811 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/AST/DeclTemplate.h b/include/clang/AST/DeclTemplate.h
index d301da8..89c0f05 100644
--- a/include/clang/AST/DeclTemplate.h
+++ b/include/clang/AST/DeclTemplate.h
@@ -1711,7 +1711,8 @@
   }
 
   /// \brief Get the sequence number for this class template partial
-  /// specialization.
+  /// specialization. Internal, only valid for specializations which
+  /// are in the specialized class template's folding set.
   unsigned getSequenceNumber() const { return SequenceNumber; }
 
   /// \brief Retrieve the member class template partial specialization from
@@ -1928,7 +1929,9 @@
 
   /// \brief Return the next partial specialization sequence number.
   unsigned getNextPartialSpecSequenceNumber() {
-    return getPartialSpecializations().size();
+    // Do not load lazy specializations here. They get numbered as they are
+    // loaded.
+    return getCommonPtr()->PartialSpecializations.size();
   }
 
   /// \brief Retrieve the partial specializations as an ordered list.
diff --git a/lib/Serialization/ASTReaderDecl.cpp b/lib/Serialization/ASTReaderDecl.cpp
index a7305c8..df6abc9 100644
--- a/lib/Serialization/ASTReaderDecl.cpp
+++ b/lib/Serialization/ASTReaderDecl.cpp
@@ -1458,9 +1458,12 @@
   if (writtenAsCanonicalDecl) {
     ClassTemplateDecl *CanonPattern = ReadDeclAs<ClassTemplateDecl>(Record,Idx);
     if (D->isCanonicalDecl()) { // It's kept in the folding set.
-      if (ClassTemplatePartialSpecializationDecl *Partial
-                        = dyn_cast<ClassTemplatePartialSpecializationDecl>(D)) {
-  CanonPattern->getCommonPtr()->PartialSpecializations.GetOrInsertNode(Partial);
+      if (ClassTemplatePartialSpecializationDecl *Partial =
+              dyn_cast<ClassTemplatePartialSpecializationDecl>(D)) {
+        Partial->SequenceNumber =
+            CanonPattern->getNextPartialSpecSequenceNumber();
+        CanonPattern->getCommonPtr()->PartialSpecializations
+            .GetOrInsertNode(Partial);
       } else {
         CanonPattern->getCommonPtr()->Specializations.GetOrInsertNode(D);
       }
@@ -1485,8 +1488,6 @@
       D->ArgsAsWritten[i] = Reader.ReadTemplateArgumentLoc(F, Record, Idx);
   }
 
-  D->SequenceNumber = Record[Idx++];
-
   // These are read/set from/to the first declaration.
   if (ThisDeclID == Redecl.getFirstID()) {
     D->InstantiatedFromMember.setPointer(
diff --git a/lib/Serialization/ASTWriterDecl.cpp b/lib/Serialization/ASTWriterDecl.cpp
index b601064..d8d351a 100644
--- a/lib/Serialization/ASTWriterDecl.cpp
+++ b/lib/Serialization/ASTWriterDecl.cpp
@@ -1174,8 +1174,6 @@
   for (int i = 0, e = D->getNumTemplateArgsAsWritten(); i != e; ++i)
     Writer.AddTemplateArgumentLoc(D->getTemplateArgsAsWritten()[i], Record);
 
-  Record.push_back(D->getSequenceNumber());
-
   // These are read/set from/to the first declaration.
   if (D->getPreviousDecl() == 0) {
     Writer.AddDeclRef(D->getInstantiatedFromMember(), Record);
diff --git a/test/Modules/Inputs/cxx-templates-a.h b/test/Modules/Inputs/cxx-templates-a.h
index 76997c7..7770d34 100644
--- a/test/Modules/Inputs/cxx-templates-a.h
+++ b/test/Modules/Inputs/cxx-templates-a.h
@@ -1,3 +1,5 @@
+@import cxx_templates_common;
+
 template<typename T> T f() { return T(); }
 template<typename T> T f(T);
 namespace N {
@@ -8,3 +10,7 @@
 template<int N> int template_param_kinds_1();
 template<template<typename T, int, int> class> int template_param_kinds_2();
 template<template<typename T, typename U, T> class> int template_param_kinds_3();
+
+template<typename T> struct SomeTemplate<T*>;
+template<typename T> struct SomeTemplate<T*> {};
+typedef SomeTemplate<int*> SomeTemplateIntPtr;
diff --git a/test/Modules/Inputs/cxx-templates-b.h b/test/Modules/Inputs/cxx-templates-b.h
index c50d705..e0f67d0 100644
--- a/test/Modules/Inputs/cxx-templates-b.h
+++ b/test/Modules/Inputs/cxx-templates-b.h
@@ -1,3 +1,5 @@
+@import cxx_templates_common;
+
 template<typename T> T f();
 template<typename T> T f(T t) { return t; }
 namespace N {
@@ -8,3 +10,7 @@
 template<typename> int template_param_kinds_1();
 template<template<typename, int, int...> class> int template_param_kinds_2();
 template<template<typename T, typename U, U> class> int template_param_kinds_3();
+
+template<typename T> struct SomeTemplate<T&> {};
+template<typename T> struct SomeTemplate<T&>;
+typedef SomeTemplate<int&> SomeTemplateIntRef;
diff --git a/test/Modules/Inputs/cxx-templates-common.h b/test/Modules/Inputs/cxx-templates-common.h
new file mode 100644
index 0000000..950a2a6
--- /dev/null
+++ b/test/Modules/Inputs/cxx-templates-common.h
@@ -0,0 +1 @@
+template<typename T> struct SomeTemplate {};
diff --git a/test/Modules/Inputs/module.map b/test/Modules/Inputs/module.map
index d2ed758..a4ac5b1 100644
--- a/test/Modules/Inputs/module.map
+++ b/test/Modules/Inputs/module.map
@@ -188,6 +188,10 @@
   header "cxx-linkage-cache.h"
 }
 
+module cxx_templates_common {
+  header "cxx-templates-common.h"
+}
+
 module cxx_templates_a {
   header "cxx-templates-a.h"
 }
diff --git a/test/Modules/cxx-templates.cpp b/test/Modules/cxx-templates.cpp
index 7d500f4..84c93df 100644
--- a/test/Modules/cxx-templates.cpp
+++ b/test/Modules/cxx-templates.cpp
@@ -17,37 +17,44 @@
   f<double>(1.0);
   f<int>();
   f(); // expected-error {{no matching function}}
-  // expected-note@Inputs/cxx-templates-b.h:1 {{couldn't infer template argument}}
-  // expected-note@Inputs/cxx-templates-b.h:2 {{requires single argument}}
+  // expected-note@Inputs/cxx-templates-b.h:3 {{couldn't infer template argument}}
+  // expected-note@Inputs/cxx-templates-b.h:4 {{requires single argument}}
 
   N::f(0);
   N::f<double>(1.0);
   N::f<int>();
   N::f(); // expected-error {{no matching function}}
-  // expected-note@Inputs/cxx-templates-a.h:4 {{couldn't infer template argument}}
-  // expected-note@Inputs/cxx-templates-a.h:5 {{requires 1 argument, but 0 were provided}}
+  // expected-note@Inputs/cxx-templates-a.h:6 {{couldn't infer template argument}}
+  // expected-note@Inputs/cxx-templates-a.h:7 {{requires 1 argument, but 0 were provided}}
 
   template_param_kinds_1<0>(); // ok, from cxx-templates-a.h
   template_param_kinds_1<int>(); // ok, from cxx-templates-b.h
 
   template_param_kinds_2<Tmpl_T_C>(); // expected-error {{no matching function}}
-  // expected-note@Inputs/cxx-templates-a.h:9 {{invalid explicitly-specified argument}}
-  // expected-note@Inputs/cxx-templates-b.h:9 {{invalid explicitly-specified argument}}
+  // expected-note@Inputs/cxx-templates-a.h:11 {{invalid explicitly-specified argument}}
+  // expected-note@Inputs/cxx-templates-b.h:11 {{invalid explicitly-specified argument}}
 
   template_param_kinds_2<Tmpl_T_I_I>(); // expected-error {{ambiguous}}
-  // expected-note@Inputs/cxx-templates-a.h:9 {{candidate}}
-  // expected-note@Inputs/cxx-templates-b.h:9 {{candidate}}
+  // expected-note@Inputs/cxx-templates-a.h:11 {{candidate}}
+  // expected-note@Inputs/cxx-templates-b.h:11 {{candidate}}
 
   // FIXME: This should be valid, but we incorrectly match the template template
   // argument against both template template parameters.
   template_param_kinds_3<Tmpl_T_T_A>(); // expected-error {{ambiguous}}
-  // expected-note@Inputs/cxx-templates-a.h:10 {{candidate}}
-  // expected-note@Inputs/cxx-templates-b.h:10 {{candidate}}
+  // expected-note@Inputs/cxx-templates-a.h:12 {{candidate}}
+  // expected-note@Inputs/cxx-templates-b.h:12 {{candidate}}
   template_param_kinds_3<Tmpl_T_T_B>(); // expected-error {{ambiguous}}
-  // expected-note@Inputs/cxx-templates-a.h:10 {{candidate}}
-  // expected-note@Inputs/cxx-templates-b.h:10 {{candidate}}
+  // expected-note@Inputs/cxx-templates-a.h:12 {{candidate}}
+  // expected-note@Inputs/cxx-templates-b.h:12 {{candidate}}
 }
 
+@import cxx_templates_common;
+
+typedef SomeTemplate<int*> SomeTemplateIntPtr;
+typedef SomeTemplate<int&> SomeTemplateIntRef;
+SomeTemplate<char*> some_template_char_ptr;
+SomeTemplate<char&> some_template_char_ref;
+
 // FIXME: There should only be two 'f's here.
 // CHECK-GLOBAL:      DeclarationName 'f'
 // CHECK-GLOBAL-NEXT: |-FunctionTemplate {{.*}} 'f'