When determining whether an expression refers to a bit-field, look
into the left-hand side of an assignment expression. This completes
most of PR3500; the only remaining part is to deal with the
GCC-specific implementation-defined behavior for "unsigned long" (and
other) bit-fields.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70623 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/Expr.cpp b/lib/AST/Expr.cpp
index d89290b..19d67bb 100644
--- a/lib/AST/Expr.cpp
+++ b/lib/AST/Expr.cpp
@@ -1379,13 +1379,19 @@
return isIntegerConstantExpr(Result, Ctx) && Result == 0;
}
-/// isBitField - Return true if this expression is a bit-field.
-bool Expr::isBitField() {
+FieldDecl *Expr::getBitField() {
Expr *E = this->IgnoreParenCasts();
+
if (MemberExpr *MemRef = dyn_cast<MemberExpr>(E))
if (FieldDecl *Field = dyn_cast<FieldDecl>(MemRef->getMemberDecl()))
- return Field->isBitField();
- return false;
+ if (Field->isBitField())
+ return Field;
+
+ if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(E))
+ if (BinOp->isAssignmentOp() && BinOp->getLHS())
+ return BinOp->getLHS()->getBitField();
+
+ return 0;
}
/// isArrow - Return true if the base expression is a pointer to vector,