Sema: Do not allow lambda expressions to appear inside of constant expressions
We would previously not diagnose this which would lead to crashes (on
very strange code).
This fixes PR17675.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@193397 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaLambda.cpp b/lib/Sema/SemaLambda.cpp
index c843da7..2e1cd10 100644
--- a/lib/Sema/SemaLambda.cpp
+++ b/lib/Sema/SemaLambda.cpp
@@ -1229,20 +1229,25 @@
CaptureInits, ArrayIndexVars,
ArrayIndexStarts, Body->getLocEnd(),
ContainsUnexpandedParameterPack);
- // C++11 [expr.prim.lambda]p2:
- // A lambda-expression shall not appear in an unevaluated operand
- // (Clause 5).
+
if (!CurContext->isDependentContext()) {
switch (ExprEvalContexts.back().Context) {
+ // C++11 [expr.prim.lambda]p2:
+ // A lambda-expression shall not appear in an unevaluated operand
+ // (Clause 5).
case Unevaluated:
case UnevaluatedAbstract:
+ // C++1y [expr.const]p2:
+ // A conditional-expression e is a core constant expression unless the
+ // evaluation of e, following the rules of the abstract machine, would
+ // evaluate [...] a lambda-expression.
+ case ConstantEvaluated:
// We don't actually diagnose this case immediately, because we
// could be within a context where we might find out later that
// the expression is potentially evaluated (e.g., for typeid).
ExprEvalContexts.back().Lambdas.push_back(Lambda);
break;
- case ConstantEvaluated:
case PotentiallyEvaluated:
case PotentiallyEvaluatedIfUsed:
break;