https://github.com/igorkudrin created https://github.com/llvm/llvm-project/pull/206219
This extracts the code that emits diagnostics when no viable function is found for allocation overload resolution to reduce the diff in #203824. >From 7a36255e4fdc031ff02eb156f55e5baee05bc374 Mon Sep 17 00:00:00 2001 From: Igor Kudrin <[email protected]> Date: Fri, 26 Jun 2026 21:42:25 -0700 Subject: [PATCH] [Sema][NFC] Extract allocation overload diagnostics This extracts the code that emits diagnostics when no viable function is found for allocation overload resolution to reduce the diff in #203824. --- clang/lib/Sema/SemaExprCXX.cpp | 133 +++++++++++++++++---------------- 1 file changed, 68 insertions(+), 65 deletions(-) diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp index 4e1652462b3ae..ea9e0b945081b 100644 --- a/clang/lib/Sema/SemaExprCXX.cpp +++ b/clang/lib/Sema/SemaExprCXX.cpp @@ -2716,6 +2716,71 @@ bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc, return false; } +static void diagnoseNoViableFunctionForAllocationOverloadResolution( + Sema &S, LookupResult &R, SourceRange Range, ArrayRef<Expr *> Args, + OverloadCandidateSet &Candidates, OverloadCandidateSet *AlignedCandidates, + Expr *AlignArg) { + // If this is an allocation of the form 'new (p) X' for some object + // pointer p (or an expression that will decay to such a pointer), + // diagnose the reason for the error. + if (!R.isClassLookup() && Args.size() == 2 && + (Args[1]->getType()->isObjectPointerType() || + Args[1]->getType()->isArrayType())) { + const QualType Arg1Type = Args[1]->getType(); + QualType UnderlyingType = S.Context.getBaseElementType(Arg1Type); + if (UnderlyingType->isPointerType()) + UnderlyingType = UnderlyingType->getPointeeType(); + if (UnderlyingType.isConstQualified()) { + S.Diag(Args[1]->getExprLoc(), + diag::err_placement_new_into_const_qualified_storage) + << Arg1Type << Args[1]->getSourceRange(); + return; + } + S.Diag(R.getNameLoc(), diag::err_need_header_before_placement_new) + << R.getLookupName() << Range; + // Listing the candidates is unlikely to be useful; skip it. + return; + } + + // Finish checking all candidates before we note any. This checking can + // produce additional diagnostics so can't be interleaved with our + // emission of notes. + // + // For an aligned allocation, separately check the aligned and unaligned + // candidates with their respective argument lists. + SmallVector<OverloadCandidate *, 32> Cands; + SmallVector<OverloadCandidate *, 32> AlignedCands; + llvm::SmallVector<Expr *, 4> AlignedArgs; + if (AlignedCandidates) { + auto IsAligned = [](OverloadCandidate &C) { + const unsigned AlignArgOffset = 1; + return C.Function->getNumParams() > AlignArgOffset && + C.Function->getParamDecl(AlignArgOffset)->getType()->isAlignValT(); + }; + auto IsUnaligned = [&](OverloadCandidate &C) { return !IsAligned(C); }; + + AlignedArgs.reserve(Args.size() + 1); + AlignedArgs.push_back(Args[0]); + AlignedArgs.push_back(AlignArg); + AlignedArgs.append(Args.begin() + 1, Args.end()); + AlignedCands = AlignedCandidates->CompleteCandidates( + S, OCD_AllCandidates, AlignedArgs, R.getNameLoc(), IsAligned); + + Cands = Candidates.CompleteCandidates(S, OCD_AllCandidates, Args, + R.getNameLoc(), IsUnaligned); + } else { + Cands = Candidates.CompleteCandidates(S, OCD_AllCandidates, Args, + R.getNameLoc()); + } + + S.Diag(R.getNameLoc(), diag::err_ovl_no_viable_function_in_call) + << R.getLookupName() << Range; + if (AlignedCandidates) + AlignedCandidates->NoteCandidates(S, AlignedArgs, AlignedCands, "", + R.getNameLoc()); + Candidates.NoteCandidates(S, Args, Cands, "", R.getNameLoc()); +} + enum class ResolveMode { Typed, Untyped }; static bool resolveAllocationOverloadInterior( Sema &S, LookupResult &R, SourceRange Range, ResolveMode Mode, @@ -2802,71 +2867,9 @@ static bool resolveAllocationOverloadInterior( Operator = nullptr; return false; } - if (Diagnose) { - // If this is an allocation of the form 'new (p) X' for some object - // pointer p (or an expression that will decay to such a pointer), - // diagnose the reason for the error. - if (!R.isClassLookup() && Args.size() == 2 && - (Args[1]->getType()->isObjectPointerType() || - Args[1]->getType()->isArrayType())) { - const QualType Arg1Type = Args[1]->getType(); - QualType UnderlyingType = S.Context.getBaseElementType(Arg1Type); - if (UnderlyingType->isPointerType()) - UnderlyingType = UnderlyingType->getPointeeType(); - if (UnderlyingType.isConstQualified()) { - S.Diag(Args[1]->getExprLoc(), - diag::err_placement_new_into_const_qualified_storage) - << Arg1Type << Args[1]->getSourceRange(); - return true; - } - S.Diag(R.getNameLoc(), diag::err_need_header_before_placement_new) - << R.getLookupName() << Range; - // Listing the candidates is unlikely to be useful; skip it. - return true; - } - - // Finish checking all candidates before we note any. This checking can - // produce additional diagnostics so can't be interleaved with our - // emission of notes. - // - // For an aligned allocation, separately check the aligned and unaligned - // candidates with their respective argument lists. - SmallVector<OverloadCandidate*, 32> Cands; - SmallVector<OverloadCandidate*, 32> AlignedCands; - llvm::SmallVector<Expr*, 4> AlignedArgs; - if (AlignedCandidates) { - auto IsAligned = [NonTypeArgumentOffset](OverloadCandidate &C) { - auto AlignArgOffset = NonTypeArgumentOffset + 1; - return C.Function->getNumParams() > AlignArgOffset && - C.Function->getParamDecl(AlignArgOffset) - ->getType() - ->isAlignValT(); - }; - auto IsUnaligned = [&](OverloadCandidate &C) { return !IsAligned(C); }; - - AlignedArgs.reserve(Args.size() + NonTypeArgumentOffset + 1); - for (unsigned Idx = 0; Idx < NonTypeArgumentOffset + 1; ++Idx) - AlignedArgs.push_back(Args[Idx]); - AlignedArgs.push_back(AlignArg); - AlignedArgs.append(Args.begin() + NonTypeArgumentOffset + 1, - Args.end()); - AlignedCands = AlignedCandidates->CompleteCandidates( - S, OCD_AllCandidates, AlignedArgs, R.getNameLoc(), IsAligned); - - Cands = Candidates.CompleteCandidates(S, OCD_AllCandidates, Args, - R.getNameLoc(), IsUnaligned); - } else { - Cands = Candidates.CompleteCandidates(S, OCD_AllCandidates, Args, - R.getNameLoc()); - } - - S.Diag(R.getNameLoc(), diag::err_ovl_no_viable_function_in_call) - << R.getLookupName() << Range; - if (AlignedCandidates) - AlignedCandidates->NoteCandidates(S, AlignedArgs, AlignedCands, "", - R.getNameLoc()); - Candidates.NoteCandidates(S, Args, Cands, "", R.getNameLoc()); - } + if (Diagnose) + diagnoseNoViableFunctionForAllocationOverloadResolution( + S, R, Range, Args, Candidates, AlignedCandidates, AlignArg); return true; case OR_Ambiguous: _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
