From: Nick Lewycky <nicholas@mxc.ca>
Date: Thu, 22 Jul 2010 17:56:53 +0000 (+0000)
Subject: Don't crash when an explicit template instantiation has no user-written
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=44db3251aec7c0e6edaf1c70d7d53a272686791a;p=clang

Don't crash when an explicit template instantiation has no user-written
arguments. This happens in clang itself where template:

  template <typename T> T const *getAs();

gets specialized with:

  template<> inline clang::TypedefType const *getAs() { ... }

and there's no TemplateArgumentList.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@109127 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/AST/RecursiveASTVisitor.h b/include/clang/AST/RecursiveASTVisitor.h
index fc62197794..0b56772c97 100644
--- a/include/clang/AST/RecursiveASTVisitor.h
+++ b/include/clang/AST/RecursiveASTVisitor.h
@@ -1318,9 +1318,13 @@ bool RecursiveASTVisitor<Derived>::TraverseFunctionHelper(FunctionDecl *D) {
       D->getTemplateSpecializationInfo()) {
     if (FTSI->getTemplateSpecializationKind() != TSK_Undeclared &&
         FTSI->getTemplateSpecializationKind() != TSK_ImplicitInstantiation) {
-      const TemplateArgumentListInfo *TALI = FTSI->TemplateArgumentsAsWritten;
-      TRY_TO(TraverseTemplateArgumentLocsHelper(TALI->getArgumentArray(),
-                                                TALI->size()));
+      // A specialization might not have explicit template arguments if it has
+      // a templated return type and concrete arguments.
+      if (const TemplateArgumentListInfo *TALI =
+          FTSI->TemplateArgumentsAsWritten) {
+        TRY_TO(TraverseTemplateArgumentLocsHelper(TALI->getArgumentArray(),
+                                                  TALI->size()));
+      }
     }
   }