Automatically discard global effects in the rare passes that add effects (#5999)

All logging/instrumentation passes need to do this, to avoid us using stale
global effects that are too low (too high is not optimal either, but at least it
cannot cause bugs).

1 files changed, 5 insertions, 0 deletions

diff --git a/src/passes/FuncCastEmulation.cpp b/src/passes/FuncCastEmulation.cpp
index 3255208fe..23eb98a8c 100644
--- a/src/passes/FuncCastEmulation.cpp
+++ b/src/passes/FuncCastEmulation.cpp
@@ -151,6 +151,11 @@ private:
 };
 
 struct FuncCastEmulation : public Pass {
+  // Changes the ABI, which alters which indirect calls will trap (normally,
+  // this should prevent traps, but it depends on code this is linked to at
+  // runtime in the case of dynamic linking etc.).
+  bool addsEffects() override { return true; }
+
   void run(Module* module) override {
     Index numParams = std::stoul(
       getPassOptions().getArgumentOrDefault("max-func-params", "16"));