don't remove unreachable nodes in vaccuum, it can alter types, and dce does that anyhow, let it do it's thing

1 files changed, 2 insertions, 0 deletions

diff --git a/src/passes/Vacuum.cpp b/src/passes/Vacuum.cpp
index 4e47ad9a3..64c7f276a 100644
--- a/src/passes/Vacuum.cpp
+++ b/src/passes/Vacuum.cpp
@@ -49,6 +49,8 @@ struct Vacuum : public WalkerPass<PostWalker<Vacuum>> {
 
   // returns nullptr if curr is dead, curr if it must stay as is, or another node if it can be replaced
   Expression* optimize(Expression* curr, bool resultUsed) {
+    // an unreachable node must not be changed
+    if (curr->type == unreachable) return curr;
     while (1) {
       switch (curr->_id) {
         case Expression::Id::NopId: return nullptr; // never needed