Fixes an IRgen ICE due to cast of null pointer to
a vla type (fixes pr7827).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@114495 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGExprScalar.cpp b/lib/CodeGen/CGExprScalar.cpp
index 73e94d1..055e3f7 100644
--- a/lib/CodeGen/CGExprScalar.cpp
+++ b/lib/CodeGen/CGExprScalar.cpp
@@ -209,8 +209,17 @@
}
Value *VisitCastExpr(CastExpr *E) {
// Make sure to evaluate VLA bounds now so that we have them for later.
- if (E->getType()->isVariablyModifiedType())
- CGF.EmitVLASize(E->getType());
+ if (E->getType()->isVariablyModifiedType()) {
+ // Implicit cast of a null pointer to a vla type need not result in vla
+ // size computation which is not always possible in any case (see pr7827).
+ bool NeedSize = true;
+ if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E))
+ NeedSize =
+ !ICE->getSubExpr()->isNullPointerConstant(CGF.getContext(),
+ Expr::NPC_ValueDependentIsNull);
+ if (NeedSize)
+ CGF.EmitVLASize(E->getType());
+ }
return EmitCastExpr(E);
}