Unverified Commit 9f3e3405 authored by Congcong Cai's avatar Congcong Cai Committed by GitHub
Browse files

[clang]Transform uninstantiated ExceptionSpec in TemplateInstantiator (#68878) 

Fixes #68543, #42496
parent 7c651a1f

clang/docs/ReleaseNotes.rst

+4 −0
Original line number Diff line number Diff line
@@ -474,6 +474,10 @@ Bug Fixes in This Version 
  cannot be used with ``Release`` mode builds. (`#68237 <https://github.com/llvm/llvm-project/issues/68237>`_).

- Fix crash in evaluating ``constexpr`` value for invalid template function.

  Fixes (`#68542 <https://github.com/llvm/llvm-project/issues/68542>`_)

- Clang will correctly evaluate ``noexcept`` expression for template functions

  of template classes. Fixes

  (`#68543 <https://github.com/llvm/llvm-project/issues/68543>`_,

  `#42496 <https://github.com/llvm/llvm-project/issues/42496>`_)

- Fixed an issue when a shift count larger than ``__INT64_MAX__``, in a right

  shift operation, could result in missing warnings about

  ``shift count >= width of type`` or internal compiler error.

clang/lib/Sema/SemaTemplateDeduction.cpp

+8 −1
Original line number Diff line number Diff line
@@ -3367,7 +3367,14 @@ Sema::TemplateDeductionResult Sema::SubstituteExplicitTemplateArguments( 
    SmallVector<QualType, 4> ExceptionStorage;

    if (getLangOpts().CPlusPlus17 &&

        SubstExceptionSpec(Function->getLocation(), EPI.ExceptionSpec,

                           ExceptionStorage, MLTAL))

                           ExceptionStorage,

                           getTemplateInstantiationArgs(

                               FunctionTemplate, nullptr, /*Final=*/true,

                               /*Innermost=*/SugaredExplicitArgumentList,

                               /*RelativeToPrimary=*/false,

                               /*Pattern=*/nullptr,

                               /*ForConstraintInstantiation=*/false,

                               /*SkipForSpecialization=*/true)))

      return TDK_SubstitutionFailure;



    *FunctionType = BuildFunctionType(ResultType, ParamTypes,

clang/lib/Sema/SemaTemplateInstantiate.cpp

+17 −2
Original line number Diff line number Diff line
@@ -1335,6 +1335,11 @@ namespace { 
    /// declaration.

    NamedDecl *TransformFirstQualifierInScope(NamedDecl *D, SourceLocation Loc);



    bool TransformExceptionSpec(SourceLocation Loc,

                                FunctionProtoType::ExceptionSpecInfo &ESI,

                                SmallVectorImpl<QualType> &Exceptions,

                                bool &Changed);



    /// Rebuild the exception declaration and register the declaration

    /// as an instantiated local.

    VarDecl *RebuildExceptionDecl(VarDecl *ExceptionDecl,
@@ -1617,6 +1622,18 @@ Decl *TemplateInstantiator::TransformDefinition(SourceLocation Loc, Decl *D) { 
  return Inst;

}



bool TemplateInstantiator::TransformExceptionSpec(

    SourceLocation Loc, FunctionProtoType::ExceptionSpecInfo &ESI,

    SmallVectorImpl<QualType> &Exceptions, bool &Changed) {

  if (ESI.Type == EST_Uninstantiated) {

    ESI.NoexceptExpr = cast<FunctionProtoType>(ESI.SourceTemplate->getType())

                           ->getNoexceptExpr();

    ESI.Type = EST_DependentNoexcept;

    Changed = true;

  }

  return inherited::TransformExceptionSpec(Loc, ESI, Exceptions, Changed);

}



NamedDecl *

TemplateInstantiator::TransformFirstQualifierInScope(NamedDecl *D,

                                                     SourceLocation Loc) {
@@ -2684,8 +2701,6 @@ bool Sema::SubstExceptionSpec(SourceLocation Loc, 
                              FunctionProtoType::ExceptionSpecInfo &ESI,

                              SmallVectorImpl<QualType> &ExceptionStorage,

                              const MultiLevelTemplateArgumentList &Args) {

  assert(ESI.Type != EST_Uninstantiated);



  bool Changed = false;

  TemplateInstantiator Instantiator(*this, Args, Loc, DeclarationName());

  return Instantiator.TransformExceptionSpec(Loc, ESI, ExceptionStorage,

clang/test/SemaCXX/dependent-noexcept-uninstantiated.cpp

0 → 100644
+11 −0
Original line number Diff line number Diff line 
// RUN: %clang_cc1 -fsyntax-only -std=c++17 %s

// expected-no-diagnostics



using A = int;

using B = char;



template <class T> struct C {

  template <class V> void f0() noexcept(sizeof(T) == sizeof(A) && sizeof(V) == sizeof(B)) {}

};



void (C<int>::*tmp1)() noexcept = &C<A>::f0<B>;