Grab-bag of bit-field fixes:
- References to ObjC bit-field ivars are bit-field lvalues;
fixes rdar://13794269, which got me started down this.
- Introduce Expr::refersToBitField, switch a couple users to
it where semantically important, and comment the difference
between this and the existing API.
- Discourage Expr::getBitField by making it a bit longer and
less general-sounding.
- Lock down on const_casts of bit-field gl-values until we
hear back from the committee as to whether they're allowed.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@181252 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaCast.cpp b/lib/Sema/SemaCast.cpp
index d6c378e..eb11a57 100644
--- a/lib/Sema/SemaCast.cpp
+++ b/lib/Sema/SemaCast.cpp
@@ -1452,7 +1452,7 @@
DestType = Self.Context.getCanonicalType(DestType);
QualType SrcType = SrcExpr->getType();
if (const ReferenceType *DestTypeTmp =DestType->getAs<ReferenceType>()) {
- if (DestTypeTmp->isLValueReferenceType() && !SrcExpr->isLValue()) {
+ if (isa<LValueReferenceType>(DestTypeTmp) && !SrcExpr->isLValue()) {
// Cannot const_cast non-lvalue to lvalue reference type. But if this
// is C-style, static_cast might find a way, so we simply suggest a
// message and tell the parent to keep searching.
@@ -1460,6 +1460,16 @@
return TC_NotApplicable;
}
+ // It's not completely clear under the standard whether we can
+ // const_cast bit-field gl-values. Doing so would not be
+ // intrinsically complicated, but for now, we say no for
+ // consistency with other compilers and await the word of the
+ // committee.
+ if (SrcExpr->refersToBitField()) {
+ msg = diag::err_bad_cxx_cast_bitfield;
+ return TC_NotApplicable;
+ }
+
// C++ 5.2.11p4: An lvalue of type T1 can be [cast] to an lvalue of type T2
// [...] if a pointer to T1 can be [cast] to the type pointer to T2.
DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index e14635e..a0998a4 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -4311,7 +4311,7 @@
IntRange::forValueOfType(C, E->getType());
}
- if (FieldDecl *BitField = E->getBitField())
+ if (FieldDecl *BitField = E->getSourceBitField())
return IntRange(BitField->getBitWidthValue(C),
BitField->getType()->isUnsignedIntegerOrEnumerationType());
@@ -4688,7 +4688,7 @@
// We want to recurse on the RHS as normal unless we're assigning to
// a bitfield.
- if (FieldDecl *Bitfield = E->getLHS()->getBitField()) {
+ if (FieldDecl *Bitfield = E->getLHS()->getSourceBitField()) {
if (AnalyzeBitFieldAssignment(S, Bitfield, E->getRHS(),
E->getOperatorLoc())) {
// Recurse, ignoring any implicit conversions on the RHS.
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 0c10658..dd05b82 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -3383,7 +3383,7 @@
isInvalid = CheckAlignOfExpr(*this, E);
} else if (ExprKind == UETT_VecStep) {
isInvalid = CheckVecStepExpr(E);
- } else if (E->getBitField()) { // C99 6.5.3.4p1.
+ } else if (E->refersToBitField()) { // C99 6.5.3.4p1.
Diag(E->getExprLoc(), diag::err_sizeof_alignof_bitfield) << 0;
isInvalid = true;
} else {
diff --git a/lib/Sema/SemaInit.cpp b/lib/Sema/SemaInit.cpp
index de93adb..9e8936e 100644
--- a/lib/Sema/SemaInit.cpp
+++ b/lib/Sema/SemaInit.cpp
@@ -3440,7 +3440,7 @@
Qualifiers T1Quals,
Qualifiers T2Quals,
bool IsLValueRef) {
- bool IsNonAddressableType = Initializer->getBitField() ||
+ bool IsNonAddressableType = Initializer->refersToBitField() ||
Initializer->refersToVectorElement();
if (IsNonAddressableType) {
@@ -5225,13 +5225,18 @@
}
case SK_BindReference:
- if (FieldDecl *BitField = CurInit.get()->getBitField()) {
- // References cannot bind to bit fields (C++ [dcl.init.ref]p5).
+ // References cannot bind to bit-fields (C++ [dcl.init.ref]p5).
+ if (CurInit.get()->refersToBitField()) {
+ // We don't necessarily have an unambiguous source bit-field.
+ FieldDecl *BitField = CurInit.get()->getSourceBitField();
S.Diag(Kind.getLocation(), diag::err_reference_bind_to_bitfield)
<< Entity.getType().isVolatileQualified()
- << BitField->getDeclName()
+ << (BitField ? BitField->getDeclName() : DeclarationName())
+ << (BitField != NULL)
<< CurInit.get()->getSourceRange();
- S.Diag(BitField->getLocation(), diag::note_bitfield_decl);
+ if (BitField)
+ S.Diag(BitField->getLocation(), diag::note_bitfield_decl);
+
return ExprError();
}
diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index c11a075..529ba12 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -1837,7 +1837,7 @@
// conversion.
using llvm::APSInt;
if (From)
- if (FieldDecl *MemberDecl = From->getBitField()) {
+ if (FieldDecl *MemberDecl = From->getSourceBitField()) {
APSInt BitWidth;
if (FromType->isIntegralType(Context) &&
MemberDecl->getBitWidth()->isIntegerConstantExpr(BitWidth, Context)) {