llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: Luohao Wang (Luohaothu) <details> <summary>Changes</summary> Fix #<!-- -->177741 Overload candidate diagnostics reserve a conversion slot for the object argument. For static methods this slot does not correspond to a real parameter, and for ill-formed declarations with an explicit object parameter we could index past the parameter list and crash in assert builds. Use isExplicitObjectMemberFunction() when mapping conversion slots to parameters and guard parameter-range computation to keep notes robust. --- Full diff: https://github.com/llvm/llvm-project/pull/177783.diff 2 Files Affected: - (modified) clang/lib/Sema/SemaOverload.cpp (+8-6) - (added) clang/test/SemaCXX/crash-GH177741.cpp (+15) ``````````diff diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp index a4f6b23066736..41b0b64409fd5 100644 --- a/clang/lib/Sema/SemaOverload.cpp +++ b/clang/lib/Sema/SemaOverload.cpp @@ -11874,7 +11874,7 @@ static void DiagnoseBadConversion(Sema &S, OverloadCandidate *Cand, !isa<CXXConstructorDecl>(Fn)) { if (I == 0) isObjectArgument = true; - else if (!Fn->hasCXXExplicitFunctionObjectParameter()) + else if (!cast<CXXMethodDecl>(Fn)->isExplicitObjectMemberFunction()) I--; } @@ -11894,7 +11894,7 @@ static void DiagnoseBadConversion(Sema &S, OverloadCandidate *Cand, llvm::any_of(Fn->parameters().take_front(I), [](const ParmVarDecl *Parm) { return Parm->isParameterPack(); }); - if (!isObjectArgument && !HasParamPack) + if (!isObjectArgument && !HasParamPack && I < Fn->getNumParams()) ToParamRange = Fn->getParamDecl(I)->getSourceRange(); if (FromTy == S.Context.OverloadTy) { @@ -12185,13 +12185,15 @@ static void DiagnoseArityMismatch(Sema &S, NamedDecl *Found, Decl *D, std::pair<OverloadCandidateKind, OverloadCandidateSelect> FnKindPair = ClassifyOverloadCandidate(S, Found, Fn, CRK_None, Description); + unsigned FirstNonObjectParamIdx = HasExplicitObjectParam ? 1 : 0; if (modeCount == 1 && !IsAddressOf && - Fn->getParamDecl(HasExplicitObjectParam ? 1 : 0)->getDeclName()) + FirstNonObjectParamIdx < Fn->getNumParams() && + Fn->getParamDecl(FirstNonObjectParamIdx)->getDeclName()) S.Diag(Fn->getLocation(), diag::note_ovl_candidate_arity_one) << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second - << Description << mode - << Fn->getParamDecl(HasExplicitObjectParam ? 1 : 0) << NumFormalArgs - << HasExplicitObjectParam << Fn->getParametersSourceRange(); + << Description << mode << Fn->getParamDecl(FirstNonObjectParamIdx) + << NumFormalArgs << HasExplicitObjectParam + << Fn->getParametersSourceRange(); else S.Diag(Fn->getLocation(), diag::note_ovl_candidate_arity) << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second diff --git a/clang/test/SemaCXX/crash-GH177741.cpp b/clang/test/SemaCXX/crash-GH177741.cpp new file mode 100644 index 0000000000000..ff40cfd57ef0f --- /dev/null +++ b/clang/test/SemaCXX/crash-GH177741.cpp @@ -0,0 +1,15 @@ +// RUN: %clang_cc1 -fsyntax-only -verify -std=c++2b %s + +// https://github.com/llvm/llvm-project/issues/177741 + +struct S { + static int operator()(this S) { return 0; } + // expected-error@-1 {{an explicit object parameter cannot appear in a static function}} + // expected-note@-2 {{candidate function not viable}} +}; + +void foo() { + S s{}; + s(0); + // expected-error@-1 {{no matching function for call to object of type 'S'}} +} `````````` </details> https://github.com/llvm/llvm-project/pull/177783 _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
