https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105152
anlauf at gcc dot gnu.org changed: What |Removed |Added ---------------------------------------------------------------------------- Keywords| |accepts-invalid Status|UNCONFIRMED |NEW Last reconfirmed| |2022-04-04 Ever confirmed|0 |1 Priority|P3 |P4 --- Comment #1 from anlauf at gcc dot gnu.org --- Confirmed. Actually we fail to diagnose the mismatch between actual and formal args and accepts invalid code. Just remove the bind(c) attribute to f in z2.