Introduce a sequence number into class template partial

specializations, which keeps track of the order in which they were
originally declared. We use this number so that we can always walk the
list of partial specializations in a predictable order during matching
or template instantiation. This also fixes a failure in Boost.Proto,
where SourceManager::isBeforeInTranslationUnit was behaving
poorly in inconsistent ways.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@102693 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 27 deletions

diff --git a/lib/Sema/SemaTemplateInstantiateDecl.cpp b/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 4575d47329..25ba2829ce 100644
--- a/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -620,21 +620,6 @@ Decl *TemplateDeclInstantiator::VisitEnumConstantDecl(EnumConstantDecl *D) {
   return 0;
 }
 
-namespace {
-  class SortDeclByLocation {
-    SourceManager &SourceMgr;
-    
-  public:
-    explicit SortDeclByLocation(SourceManager &SourceMgr) 
-      : SourceMgr(SourceMgr) { }
-    
-    bool operator()(const Decl *X, const Decl *Y) const {
-      return SourceMgr.isBeforeInTranslationUnit(X->getLocation(),
-                                                 Y->getLocation());
-    }
-  };
-}
-
 Decl *TemplateDeclInstantiator::VisitClassTemplateDecl(ClassTemplateDecl *D) {
   bool isFriend = (D->getFriendObjectKind() != Decl::FOK_None);
 
@@ -791,19 +776,10 @@ Decl *TemplateDeclInstantiator::VisitClassTemplateDecl(ClassTemplateDecl *D) {
   
   Owner->addDecl(Inst);
   
-  // First, we sort the partial specializations by location, so 
-  // that we instantiate them in the order they were declared.
-  llvm::SmallVector<ClassTemplatePartialSpecializationDecl *, 4> PartialSpecs;
-  for (llvm::FoldingSet<ClassTemplatePartialSpecializationDecl>::iterator
-         P = D->getPartialSpecializations().begin(), 
-         PEnd = D->getPartialSpecializations().end();
-       P != PEnd; ++P)
-    PartialSpecs.push_back(&*P);
-  std::sort(PartialSpecs.begin(), PartialSpecs.end(),
-            SortDeclByLocation(SemaRef.SourceMgr));
-  
   // Instantiate all of the partial specializations of this member class 
   // template.
+  llvm::SmallVector<ClassTemplatePartialSpecializationDecl *, 4> PartialSpecs;
+  D->getPartialSpecializations(PartialSpecs);
   for (unsigned I = 0, N = PartialSpecs.size(); I != N; ++I)
     InstantiateClassTemplatePartialSpecialization(Inst, PartialSpecs[I]);
   
@@ -1768,7 +1744,8 @@ TemplateDeclInstantiator::InstantiateClassTemplatePartialSpecialization(
                                                      Converted,
                                                      InstTemplateArgs,
                                                      CanonType,
-                                                     0);
+                                                     0,
+                             ClassTemplate->getPartialSpecializations().size());
   // Substitute the nested name specifier, if any.
   if (SubstQualifier(PartialSpec, InstPartialSpec))
     return 0;