add test for #90192

Fixes #90192

Author: matthiaskrgr

tests/ui/polymorphization/issue-74614.rs

@@ -1,4 +1,7 @@
-//@ compile-flags:-Zpolymorphize=on
+//@ revisions: mir-opt no-opt
+//@ [no-opt]compile-flags:-Zpolymorphize=on
+// used to ICE, see #90192:
+//@ [mir-opt]compile-flags:-Zpolymorphize=on -Zmir-opt-level=3
 //@ build-pass
 
 fn test<T>() {