When diagnosing an ambiguity, only note the candidates that contribute
to the ambiguity, rather than noting all viable candidates.
diff --git a/clang/lib/Sema/SemaCast.cpp b/clang/lib/Sema/SemaCast.cpp
index 0ebb5c6..2ab0a11 100644
--- a/clang/lib/Sema/SemaCast.cpp
+++ b/clang/lib/Sema/SemaCast.cpp
@@ -423,7 +423,7 @@
case OR_Ambiguous:
msg = diag::err_ovl_ambiguous_conversion_in_cast;
- howManyCandidates = OCD_ViableCandidates;
+ howManyCandidates = OCD_AmbiguousCandidates;
break;
case OR_Deleted:
diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index 9aae928..18efd83 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -2323,7 +2323,7 @@
PartialDiagnosticAt(R.getNameLoc(),
S.PDiag(diag::err_ovl_ambiguous_call)
<< R.getLookupName() << Range),
- S, OCD_ViableCandidates, Args);
+ S, OCD_AmbiguousCandidates, Args);
}
return true;
@@ -3513,7 +3513,7 @@
PartialDiagnosticAt(R.getNameLoc(),
S.PDiag(diag::err_ovl_ambiguous_call)
<< R.getLookupName() << Range),
- S, OCD_ViableCandidates, Args);
+ S, OCD_AmbiguousCandidates, Args);
return true;
case OR_Deleted: {
diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp
index 10cb7ac..1296e76 100644
--- a/clang/lib/Sema/SemaInit.cpp
+++ b/clang/lib/Sema/SemaInit.cpp
@@ -6154,7 +6154,7 @@
<< (int)Entity.getKind()
<< CurInitExpr->getType()
<< CurInitExpr->getSourceRange()),
- S, OCD_ViableCandidates, CurInitExpr);
+ S, OCD_AmbiguousCandidates, CurInitExpr);
return ExprError();
case OR_Deleted:
@@ -6295,7 +6295,7 @@
case OR_Ambiguous:
CandidateSet.NoteCandidates(PartialDiagnosticAt(Loc, Diag), S,
- OCD_ViableCandidates, CurInitExpr);
+ OCD_AmbiguousCandidates, CurInitExpr);
break;
case OR_Deleted:
@@ -8806,7 +8806,7 @@
: (S.PDiag(diag::err_ref_init_ambiguous)
<< DestType << OnlyArg->getType()
<< Args[0]->getSourceRange())),
- S, OCD_ViableCandidates, Args);
+ S, OCD_AmbiguousCandidates, Args);
break;
case OR_No_Viable_Function: {
@@ -9000,7 +9000,7 @@
PartialDiagnosticAt(Kind.getLocation(),
S.PDiag(diag::err_ovl_ambiguous_init)
<< DestType << ArgsRange),
- S, OCD_ViableCandidates, Args);
+ S, OCD_AmbiguousCandidates, Args);
break;
case OR_No_Viable_Function:
@@ -9863,7 +9863,7 @@
Kind.getLocation(),
PDiag(diag::err_deduced_class_template_ctor_ambiguous)
<< TemplateName),
- *this, OCD_ViableCandidates, Inits);
+ *this, OCD_AmbiguousCandidates, Inits);
return QualType();
case OR_No_Viable_Function: {
diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index b79855a..4417d22 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -1357,7 +1357,7 @@
ICS.Ambiguous.setToType(ToType);
for (OverloadCandidateSet::iterator Cand = Conversions.begin();
Cand != Conversions.end(); ++Cand)
- if (Cand->Viable)
+ if (Cand->Best)
ICS.Ambiguous.addConversion(Cand->FoundDecl, Cand->Function);
break;
@@ -3578,7 +3578,10 @@
(OvResult == OR_No_Viable_Function && !CandidateSet.empty())))
return false;
- auto Cands = CandidateSet.CompleteCandidates(*this, OCD_AllCandidates, From);
+ auto Cands = CandidateSet.CompleteCandidates(
+ *this,
+ OvResult == OR_Ambiguous ? OCD_AmbiguousCandidates : OCD_AllCandidates,
+ From);
if (OvResult == OR_Ambiguous)
Diag(From->getBeginLoc(), diag::err_typecheck_ambiguous_condition)
<< From->getType() << ToType << From->getSourceRange();
@@ -4602,7 +4605,7 @@
ICS.setAmbiguous();
for (OverloadCandidateSet::iterator Cand = CandidateSet.begin();
Cand != CandidateSet.end(); ++Cand)
- if (Cand->Viable)
+ if (Cand->Best)
ICS.Ambiguous.addConversion(Cand->FoundDecl, Cand->Function);
return true;
@@ -9653,11 +9656,13 @@
// Find the best viable function.
Best = end();
- for (auto *Cand : Candidates)
+ for (auto *Cand : Candidates) {
+ Cand->Best = false;
if (Cand->Viable)
if (Best == end() ||
isBetterOverloadCandidate(S, *Cand, *Best, Loc, Kind))
Best = Cand;
+ }
// If we didn't find any viable functions, abort.
if (Best == end())
@@ -9665,22 +9670,33 @@
llvm::SmallVector<const NamedDecl *, 4> EquivalentCands;
+ llvm::SmallVector<OverloadCandidate*, 4> PendingBest;
+ PendingBest.push_back(&*Best);
+ Best->Best = true;
+
// Make sure that this function is better than every other viable
// function. If not, we have an ambiguity.
- for (auto *Cand : Candidates) {
- if (Cand->Viable && Cand != Best &&
- !isBetterOverloadCandidate(S, *Best, *Cand, Loc, Kind)) {
- if (S.isEquivalentInternalLinkageDeclaration(Best->Function,
- Cand->Function)) {
- EquivalentCands.push_back(Cand->Function);
- continue;
- }
+ while (!PendingBest.empty()) {
+ auto *Curr = PendingBest.pop_back_val();
+ for (auto *Cand : Candidates) {
+ if (Cand->Viable && !Cand->Best &&
+ !isBetterOverloadCandidate(S, *Curr, *Cand, Loc, Kind)) {
+ PendingBest.push_back(Cand);
+ Cand->Best = true;
- Best = end();
- return OR_Ambiguous;
+ if (S.isEquivalentInternalLinkageDeclaration(Cand->Function,
+ Curr->Function))
+ EquivalentCands.push_back(Cand->Function);
+ else
+ Best = end();
+ }
}
}
+ // If we found more than one best candidate, this is ambiguous.
+ if (Best == end())
+ return OR_Ambiguous;
+
// Best is the best viable function.
if (Best->Function && Best->Function->isDeleted())
return OR_Deleted;
@@ -11080,15 +11096,30 @@
for (iterator Cand = begin(), LastCand = end(); Cand != LastCand; ++Cand) {
if (!Filter(*Cand))
continue;
- if (Cand->Viable)
- Cands.push_back(Cand);
- else if (OCD == OCD_AllCandidates) {
- CompleteNonViableCandidate(S, Cand, Args, Kind);
- if (Cand->Function || Cand->IsSurrogate)
- Cands.push_back(Cand);
- // Otherwise, this a non-viable builtin candidate. We do not, in general,
- // want to list every possible builtin candidate.
+ switch (OCD) {
+ case OCD_AllCandidates:
+ if (!Cand->Viable) {
+ if (!Cand->Function && !Cand->IsSurrogate) {
+ // This a non-viable builtin candidate. We do not, in general,
+ // want to list every possible builtin candidate.
+ continue;
+ }
+ CompleteNonViableCandidate(S, Cand, Args, Kind);
+ }
+ break;
+
+ case OCD_ViableCandidates:
+ if (!Cand->Viable)
+ continue;
+ break;
+
+ case OCD_AmbiguousCandidates:
+ if (!Cand->Best)
+ continue;
+ break;
}
+
+ Cands.push_back(Cand);
}
llvm::stable_sort(
@@ -12453,7 +12484,7 @@
PartialDiagnosticAt(Fn->getBeginLoc(),
SemaRef.PDiag(diag::err_ovl_ambiguous_call)
<< ULE->getName() << Fn->getSourceRange()),
- SemaRef, OCD_ViableCandidates, Args);
+ SemaRef, OCD_AmbiguousCandidates, Args);
break;
case OR_Deleted: {
@@ -12699,7 +12730,7 @@
PDiag(diag::err_ovl_ambiguous_oper_unary)
<< UnaryOperator::getOpcodeStr(Opc)
<< Input->getType() << Input->getSourceRange()),
- *this, OCD_ViableCandidates, ArgsArray,
+ *this, OCD_AmbiguousCandidates, ArgsArray,
UnaryOperator::getOpcodeStr(Opc), OpLoc);
return ExprError();
@@ -13108,7 +13139,7 @@
<< Args[1]->getType()
<< Args[0]->getSourceRange()
<< Args[1]->getSourceRange()),
- *this, OCD_ViableCandidates, Args, BinaryOperator::getOpcodeStr(Opc),
+ *this, OCD_AmbiguousCandidates, Args, BinaryOperator::getOpcodeStr(Opc),
OpLoc);
return ExprError();
@@ -13293,7 +13324,7 @@
<< Args[1]->getType()
<< Args[0]->getSourceRange()
<< Args[1]->getSourceRange()),
- *this, OCD_ViableCandidates, Args, "[]", LLoc);
+ *this, OCD_AmbiguousCandidates, Args, "[]", LLoc);
return ExprError();
case OR_Deleted:
@@ -13485,7 +13516,7 @@
PartialDiagnosticAt(UnresExpr->getMemberLoc(),
PDiag(diag::err_ovl_ambiguous_member_call)
<< DeclName << MemExprE->getSourceRange()),
- *this, OCD_AllCandidates, Args);
+ *this, OCD_AmbiguousCandidates, Args);
// FIXME: Leaking incoming expressions!
return ExprError();
@@ -13717,7 +13748,7 @@
PDiag(diag::err_ovl_ambiguous_object_call)
<< Object.get()->getType()
<< Object.get()->getSourceRange()),
- *this, OCD_ViableCandidates, Args);
+ *this, OCD_AmbiguousCandidates, Args);
break;
case OR_Deleted:
@@ -13952,7 +13983,7 @@
PartialDiagnosticAt(OpLoc, PDiag(diag::err_ovl_ambiguous_oper_unary)
<< "->" << Base->getType()
<< Base->getSourceRange()),
- *this, OCD_ViableCandidates, Base);
+ *this, OCD_AmbiguousCandidates, Base);
return ExprError();
case OR_Deleted:
@@ -14032,7 +14063,7 @@
CandidateSet.NoteCandidates(
PartialDiagnosticAt(R.getNameLoc(), PDiag(diag::err_ovl_ambiguous_call)
<< R.getLookupName()),
- *this, OCD_ViableCandidates, Args);
+ *this, OCD_AmbiguousCandidates, Args);
return ExprError();
}