commit b41171b70b214ee529b01c3f6166e0b82229dabf
author Chandler Carruth <chandlerc@gmail.com> Thu May 03 23:49:05 2012 +0000
committer Chandler Carruth <chandlerc@gmail.com> Thu May 03 23:49:05 2012 +0000
tree a403deddd10616f8e4c4ddac487fc95d2006c9d4
parent e31772fc44f41400e2106f31c9128657c30f0699

Fix non-deterministic iteration order when walking the specializations
of templates by using the newly introduce FoldingSetVector. This
preserves insertion order for all iteration of specializations.

I've also included a somewhat terrifying testcase that rapidly builds up
a large number of functions. This is enough that any system with ASLR
will have non-deterministic debug information generated for the test
case without the fix here as the debug information is generated in part
by walking these specializations.

llvm-svn: 156133

clang/lib/AST/DeclTemplate.cpp

diff --git a/clang/lib/AST/DeclTemplate.cpp b/clang/lib/AST/DeclTemplate.cpp
index 4590195..9a338e5 100644
--- a/clang/lib/AST/DeclTemplate.cpp
+++ b/clang/lib/AST/DeclTemplate.cpp
@@ -145,7 +145,7 @@
 template <class EntryType>
 typename RedeclarableTemplateDecl::SpecEntryTraits<EntryType>::DeclType*
 RedeclarableTemplateDecl::findSpecializationImpl(
-                                 llvm::FoldingSet<EntryType> &Specs,
+                                 llvm::FoldingSetVector<EntryType> &Specs,
                                  const TemplateArgument *Args, unsigned NumArgs,
                                  void *&InsertPos) {
   typedef SpecEntryTraits<EntryType> SETraits;
@@ -298,13 +298,13 @@
   }
 }
 
-llvm::FoldingSet<ClassTemplateSpecializationDecl> &
+llvm::FoldingSetVector<ClassTemplateSpecializationDecl> &
 ClassTemplateDecl::getSpecializations() {
   LoadLazySpecializations();
   return getCommonPtr()->Specializations;
 }  
 
-llvm::FoldingSet<ClassTemplatePartialSpecializationDecl> &
+llvm::FoldingSetVector<ClassTemplatePartialSpecializationDecl> &
 ClassTemplateDecl::getPartialSpecializations() {
   LoadLazySpecializations();
   return getCommonPtr()->PartialSpecializations;
@@ -363,11 +363,11 @@
 
 void ClassTemplateDecl::getPartialSpecializations(
           SmallVectorImpl<ClassTemplatePartialSpecializationDecl *> &PS) {
-  llvm::FoldingSet<ClassTemplatePartialSpecializationDecl> &PartialSpecs
+  llvm::FoldingSetVector<ClassTemplatePartialSpecializationDecl> &PartialSpecs
     = getPartialSpecializations();
   PS.clear();
   PS.resize(PartialSpecs.size());
-  for (llvm::FoldingSet<ClassTemplatePartialSpecializationDecl>::iterator
+  for (llvm::FoldingSetVector<ClassTemplatePartialSpecializationDecl>::iterator
        P = PartialSpecs.begin(), PEnd = PartialSpecs.end();
        P != PEnd; ++P) {
     assert(!PS[P->getSequenceNumber()]);
@@ -378,7 +378,8 @@
 ClassTemplatePartialSpecializationDecl *
 ClassTemplateDecl::findPartialSpecialization(QualType T) {
   ASTContext &Context = getASTContext();
-  typedef llvm::FoldingSet<ClassTemplatePartialSpecializationDecl>::iterator
+  using llvm::FoldingSetVector;
+  typedef FoldingSetVector<ClassTemplatePartialSpecializationDecl>::iterator
     partial_spec_iterator;
   for (partial_spec_iterator P = getPartialSpecializations().begin(),
                           PEnd = getPartialSpecializations().end();
@@ -394,7 +395,7 @@
 ClassTemplateDecl::findPartialSpecInstantiatedFromMember(
                                     ClassTemplatePartialSpecializationDecl *D) {
   Decl *DCanon = D->getCanonicalDecl();
-  for (llvm::FoldingSet<ClassTemplatePartialSpecializationDecl>::iterator
+  for (llvm::FoldingSetVector<ClassTemplatePartialSpecializationDecl>::iterator
             P = getPartialSpecializations().begin(),
          PEnd = getPartialSpecializations().end();
        P != PEnd; ++P) {