Commit 8f456a6c authored by Bill Wendling's avatar Bill Wendling
Browse files

Merging r197305: 

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r197305 | rsmith | 2013-12-13 19:18:05 -0800 (Fri, 13 Dec 2013) | 7 lines

PR18246: When performing template argument deduction to decide which template
is specialized by an explicit specialization, start from the first declaration
in case we've got a member of a class template (redeclarations might not number
the template parameters the same way).

Our recover here is still far from ideal.

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llvm-svn: 197319
parent 56206980

clang/lib/Sema/SemaTemplate.cpp

+3 −3
Original line number Diff line number Diff line
@@ -6523,9 +6523,9 @@ bool Sema::CheckFunctionTemplateSpecialization( 
      // FIXME: It is somewhat wasteful to build

      TemplateDeductionInfo Info(FailedCandidates.getLocation());

      FunctionDecl *Specialization = 0;

      if (TemplateDeductionResult TDK

            = DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs, FT,

                                      Specialization, Info)) {

      if (TemplateDeductionResult TDK = DeduceTemplateArguments(

              cast<FunctionTemplateDecl>(FunTmpl->getFirstDecl()),

              ExplicitTemplateArgs, FT, Specialization, Info)) {

        // Template argument deduction failed; record why it failed, so

        // that we can provide nifty diagnostics.

        FailedCandidates.addCandidate()

clang/test/SemaTemplate/explicit-specialization-member.cpp

+19 −0
Original line number Diff line number Diff line
@@ -28,3 +28,22 @@ namespace PR12331 { 
  };

  template<> struct S<int>::U { static const int n = sizeof(int); }; // expected-error {{explicit specialization of 'U' after instantiation}}

}



namespace PR18246 {

  template<typename T>

  class Baz {

  public:

    template<int N> void bar();

  };



  template<typename T>

  template<int N>

  void Baz<T>::bar() {

  }



  // FIXME: Don't suggest the 'template<>' correction here, because this cannot

  // be an explicit specialization.

  template<typename T>

  void Baz<T>::bar<0>() { // expected-error {{requires 'template<>'}}

  }

}