Fix a crash-on-valid that has been here for a very long time:
const int &x = x;
This crashed by inifinetly recursing within the lvalue evaluation
routine. I've added a (somewhat) braindead way of preventing this
recursion. If folks have better suggestions for how to avoid it I'm all
ears.
That said, we have some work to do. This doesn't trigger a single
warning for uninitialized, self-initialized or otherwise completely
wrong code. In some senses, the crash was almost better.
llvm-svn: 138239
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index fdcff0a..2cd85a1 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -447,6 +447,7 @@
class LValueExprEvaluator
: public ExprEvaluatorBase<LValueExprEvaluator, bool> {
LValue &Result;
+ const Decl *PrevDecl;
bool Success(const Expr *E) {
Result.Base = E;
@@ -456,7 +457,7 @@
public:
LValueExprEvaluator(EvalInfo &info, LValue &Result) :
- ExprEvaluatorBaseTy(info), Result(Result) {}
+ ExprEvaluatorBaseTy(info), Result(Result), PrevDecl(0) {}
bool Success(const APValue &V, const Expr *E) {
Result.setFrom(V);
@@ -501,10 +502,16 @@
return Success(E);
// Reference parameters can refer to anything even if they have an
// "initializer" in the form of a default argument.
- if (!isa<ParmVarDecl>(VD))
+ if (!isa<ParmVarDecl>(VD)) {
// FIXME: Check whether VD might be overridden!
+
+ // Check for recursive initializers of references.
+ if (PrevDecl == VD)
+ return Error(E);
+ PrevDecl = VD;
if (const Expr *Init = VD->getAnyInitializer())
return Visit(Init);
+ }
}
return ExprEvaluatorBaseTy::VisitDeclRefExpr(E);