Introduce a specific representation for the ambiguous implicit conversion
sequence. Lots of small relevant changes. Fixes some serious problems with
ambiguous conversions; also possibly improves associated diagnostics.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@93214 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index 6407441..e655184 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -1075,7 +1075,7 @@
AssignmentAction Action, bool AllowExplicit,
bool Elidable,
ImplicitConversionSequence& ICS) {
- ICS.ConversionKind = ImplicitConversionSequence::BadConversion;
+ ICS.setBad();
if (Elidable && getLangOptions().CPlusPlus0x) {
ICS = TryImplicitConversion(From, ToType,
/*SuppressUserConversions=*/false,
@@ -1083,7 +1083,7 @@
/*ForceRValue=*/true,
/*InOverloadResolution=*/false);
}
- if (ICS.ConversionKind == ImplicitConversionSequence::BadConversion) {
+ if (ICS.isBad()) {
ICS = TryImplicitConversion(From, ToType,
/*SuppressUserConversions=*/false,
AllowExplicit,
@@ -1103,7 +1103,7 @@
Sema::PerformImplicitConversion(Expr *&From, QualType ToType,
const ImplicitConversionSequence &ICS,
AssignmentAction Action, bool IgnoreBaseAccess) {
- switch (ICS.ConversionKind) {
+ switch (ICS.getKind()) {
case ImplicitConversionSequence::StandardConversion:
if (PerformImplicitConversion(From, ToType, ICS.Standard, Action,
IgnoreBaseAccess))
@@ -1157,6 +1157,12 @@
return PerformImplicitConversion(From, ToType, ICS.UserDefined.After,
AA_Converting, IgnoreBaseAccess);
}
+
+ case ImplicitConversionSequence::AmbiguousConversion:
+ DiagnoseAmbiguousConversion(ICS, From->getExprLoc(),
+ PDiag(diag::err_typecheck_ambiguous_condition)
+ << From->getSourceRange());
+ return true;
case ImplicitConversionSequence::EllipsisConversion:
assert(false && "Cannot perform an ellipsis conversion");
@@ -1474,14 +1480,18 @@
/// \brief Get the target type of a standard or user-defined conversion.
static QualType TargetType(const ImplicitConversionSequence &ICS) {
- assert((ICS.ConversionKind ==
- ImplicitConversionSequence::StandardConversion ||
- ICS.ConversionKind ==
- ImplicitConversionSequence::UserDefinedConversion) &&
- "function only valid for standard or user-defined conversions");
- if (ICS.ConversionKind == ImplicitConversionSequence::StandardConversion)
- return QualType::getFromOpaquePtr(ICS.Standard.ToTypePtr);
- return QualType::getFromOpaquePtr(ICS.UserDefined.After.ToTypePtr);
+ switch (ICS.getKind()) {
+ case ImplicitConversionSequence::StandardConversion:
+ return ICS.Standard.getToType();
+ case ImplicitConversionSequence::UserDefinedConversion:
+ return ICS.UserDefined.After.getToType();
+ case ImplicitConversionSequence::AmbiguousConversion:
+ return ICS.Ambiguous.getToType();
+ case ImplicitConversionSequence::EllipsisConversion:
+ case ImplicitConversionSequence::BadConversion:
+ llvm_unreachable("function not valid for ellipsis or bad conversions");
+ }
+ return QualType(); // silence warnings
}
/// \brief Try to convert a type to another according to C++0x 5.16p3.
@@ -1511,19 +1521,16 @@
/*ForceRValue=*/false,
&ICS))
{
- assert((ICS.ConversionKind ==
- ImplicitConversionSequence::StandardConversion ||
- ICS.ConversionKind ==
- ImplicitConversionSequence::UserDefinedConversion) &&
+ assert((ICS.isStandard() || ICS.isUserDefined()) &&
"expected a definite conversion");
bool DirectBinding =
- ICS.ConversionKind == ImplicitConversionSequence::StandardConversion ?
- ICS.Standard.DirectBinding : ICS.UserDefined.After.DirectBinding;
+ ICS.isStandard() ? ICS.Standard.DirectBinding
+ : ICS.UserDefined.After.DirectBinding;
if (DirectBinding)
return false;
}
}
- ICS.ConversionKind = ImplicitConversionSequence::BadConversion;
+ ICS.setBad();
// -- If E2 is an rvalue, or if the conversion above cannot be done:
// -- if E1 and E2 have class type, and the underlying class types are
// the same or one is a base class of the other:
@@ -1619,8 +1626,7 @@
/// handles the reference binding specially.
static bool ConvertForConditional(Sema &Self, Expr *&E,
const ImplicitConversionSequence &ICS) {
- if (ICS.ConversionKind == ImplicitConversionSequence::StandardConversion &&
- ICS.Standard.ReferenceBinding) {
+ if (ICS.isStandard() && ICS.Standard.ReferenceBinding) {
assert(ICS.Standard.DirectBinding &&
"TryClassUnification should never generate indirect ref bindings");
// FIXME: CheckReferenceInit should be able to reuse the ICS instead of
@@ -1632,8 +1638,7 @@
/*AllowExplicit=*/false,
/*ForceRValue=*/false);
}
- if (ICS.ConversionKind == ImplicitConversionSequence::UserDefinedConversion &&
- ICS.UserDefined.After.ReferenceBinding) {
+ if (ICS.isUserDefined() && ICS.UserDefined.After.ReferenceBinding) {
assert(ICS.UserDefined.After.DirectBinding &&
"TryClassUnification should never generate indirect ref bindings");
return Self.CheckReferenceInit(E, Self.Context.getLValueReferenceType(
@@ -1721,10 +1726,8 @@
if (TryClassUnification(*this, RHS, LHS, QuestionLoc, ICSRightToLeft))
return QualType();
- bool HaveL2R = ICSLeftToRight.ConversionKind !=
- ImplicitConversionSequence::BadConversion;
- bool HaveR2L = ICSRightToLeft.ConversionKind !=
- ImplicitConversionSequence::BadConversion;
+ bool HaveL2R = !ICSLeftToRight.isBad();
+ bool HaveR2L = !ICSRightToLeft.isBad();
// If both can be converted, [...] the program is ill-formed.
if (HaveL2R && HaveR2L) {
Diag(QuestionLoc, diag::err_conditional_ambiguous)
@@ -1938,8 +1941,8 @@
/*InOverloadResolution=*/false);
ImplicitConversionSequence E1ToC2, E2ToC2;
- E1ToC2.ConversionKind = ImplicitConversionSequence::BadConversion;
- E2ToC2.ConversionKind = ImplicitConversionSequence::BadConversion;
+ E1ToC2.setBad();
+ E2ToC2.setBad();
if (Context.getCanonicalType(Composite1) !=
Context.getCanonicalType(Composite2)) {
E1ToC2 = TryImplicitConversion(E1, Composite2,
@@ -1954,14 +1957,8 @@
/*InOverloadResolution=*/false);
}
- bool ToC1Viable = E1ToC1.ConversionKind !=
- ImplicitConversionSequence::BadConversion
- && E2ToC1.ConversionKind !=
- ImplicitConversionSequence::BadConversion;
- bool ToC2Viable = E1ToC2.ConversionKind !=
- ImplicitConversionSequence::BadConversion
- && E2ToC2.ConversionKind !=
- ImplicitConversionSequence::BadConversion;
+ bool ToC1Viable = !E1ToC1.isBad() && !E2ToC1.isBad();
+ bool ToC2Viable = !E1ToC2.isBad() && !E2ToC2.isBad();
if (ToC1Viable && !ToC2Viable) {
if (!PerformImplicitConversion(E1, Composite1, E1ToC1, Sema::AA_Converting) &&
!PerformImplicitConversion(E2, Composite1, E2ToC1, Sema::AA_Converting))