From 8a50fe0d76b0f245b4cdd599230f2ee023be82cd Mon Sep 17 00:00:00 2001
From: Douglas Gregor <dgregor@apple.com>
Date: Mon, 2 Jul 2012 21:00:41 +0000
Subject: [PATCH] Be more eager about setting the 'Invalid' bit on an invalid
 class template instantiation. I wasn't able to reproduce this down to
 anything small enough to put in our test suite, but it's "obviously" okay to
 set the invalid bit earlier and precludes a
 known-broken-but-not-marked-broken class from being used elsewhere.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@159584 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Sema/SemaDeclCXX.cpp             |  2 ++
 lib/Sema/SemaTemplateInstantiate.cpp | 23 ++++++++++-------------
 test/SemaCXX/PR9460.cpp              |  6 +++---
 3 files changed, 15 insertions(+), 16 deletions(-)

diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index babeaf7bd7..ad650751d6 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -1119,6 +1119,8 @@ Sema::ActOnBaseSpecifier(Decl *classdecl, SourceRange SpecifierRange,
                                                       Virtual, Access, TInfo,
                                                       EllipsisLoc))
     return BaseSpec;
+  else
+    Class->setInvalidDecl();
 
   return true;
 }
diff --git a/lib/Sema/SemaTemplateInstantiate.cpp b/lib/Sema/SemaTemplateInstantiate.cpp
index b80aaa2bbc..8973916f37 100644
--- a/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/lib/Sema/SemaTemplateInstantiate.cpp
@@ -1832,8 +1832,6 @@ Sema::InstantiateClass(SourceLocation PointOfInstantiation,
                        const MultiLevelTemplateArgumentList &TemplateArgs,
                        TemplateSpecializationKind TSK,
                        bool Complain) {
-  bool Invalid = false;
-
   CXXRecordDecl *PatternDef
     = cast_or_null<CXXRecordDecl>(Pattern->getDefinition());
   if (DiagnoseUninstantiableTemplate(*this, PointOfInstantiation, Instantiation,
@@ -1879,7 +1877,7 @@ Sema::InstantiateClass(SourceLocation PointOfInstantiation,
 
   // Do substitution on the base class specifiers.
   if (SubstBaseSpecifiers(Instantiation, Pattern, TemplateArgs))
-    Invalid = true;
+    Instantiation->setInvalidDecl();
 
   TemplateDeclInstantiator Instantiator(*this, Instantiation, TemplateArgs);
   SmallVector<Decl*, 4> Fields;
@@ -1905,7 +1903,7 @@ Sema::InstantiateClass(SourceLocation PointOfInstantiation,
       continue;
 
     if ((*Member)->isInvalidDecl()) {
-      Invalid = true; 
+      Instantiation->setInvalidDecl(); 
       continue;
     }
 
@@ -1932,11 +1930,12 @@ Sema::InstantiateClass(SourceLocation PointOfInstantiation,
       }
 
       if (NewMember->isInvalidDecl())
-        Invalid = true;
+        Instantiation->setInvalidDecl();
     } else {
       // FIXME: Eventually, a NULL return will mean that one of the
-      // instantiations was a semantic disaster, and we'll want to set Invalid =
-      // true. For now, we expect to skip some members that we can't yet handle.
+      // instantiations was a semantic disaster, and we'll want to mark the
+      // declaration invalid.
+      // For now, we expect to skip some members that we can't yet handle.
     }
   }
 
@@ -1995,9 +1994,7 @@ Sema::InstantiateClass(SourceLocation PointOfInstantiation,
     Instantiation->setRBraceLoc(Pattern->getRBraceLoc());
   }
 
-  if (Instantiation->isInvalidDecl())
-    Invalid = true;
-  else {
+  if (!Instantiation->isInvalidDecl()) {
     // Instantiate any out-of-line class template partial
     // specializations now.
     for (TemplateDeclInstantiator::delayed_partial_spec_iterator 
@@ -2007,7 +2004,7 @@ Sema::InstantiateClass(SourceLocation PointOfInstantiation,
       if (!Instantiator.InstantiateClassTemplatePartialSpecialization(
                                                                 P->first,
                                                                 P->second)) {
-        Invalid = true;
+        Instantiation->setInvalidDecl();
         break;
       }
     }
@@ -2016,7 +2013,7 @@ Sema::InstantiateClass(SourceLocation PointOfInstantiation,
   // Exit the scope of this instantiation.
   SavedContext.pop();
 
-  if (!Invalid) {
+  if (!Instantiation->isInvalidDecl()) {
     Consumer.HandleTagDeclDefinition(Instantiation);
 
     // Always emit the vtable for an explicit instantiation definition
@@ -2025,7 +2022,7 @@ Sema::InstantiateClass(SourceLocation PointOfInstantiation,
       MarkVTableUsed(PointOfInstantiation, Instantiation, true);
   }
 
-  return Invalid;
+  return Instantiation->isInvalidDecl();
 }
 
 /// \brief Instantiate the definition of an enum from a given pattern.
diff --git a/test/SemaCXX/PR9460.cpp b/test/SemaCXX/PR9460.cpp
index 0dd8446770..5b8b7b2cf6 100644
--- a/test/SemaCXX/PR9460.cpp
+++ b/test/SemaCXX/PR9460.cpp
@@ -8,11 +8,11 @@ struct basic_string{
   basic_string(aT*);
 };
 
-struct runtime_error{
-  runtime_error(
+struct runtime_error{ // expected-note{{candidate constructor}}
+  runtime_error( // expected-note{{candidate constructor}}
 basic_string<char> struct{ // expected-error {{cannot combine with previous 'type-name' declaration specifier}}
 a(){ // expected-error {{requires a type specifier}}
-  runtime_error(0);
+  runtime_error(0); // expected-error{{no matching conversion for functional-style cast from 'int' to 'runtime_error'}}
 }
 }
 );
-- 
2.40.0