Hi,

This is a repost of the patch at https://gcc.gnu.org/pipermail/gcc-patches/2022-September/600887.html
which never really got green light, but I stopped pushing because stage 1 was closing and I was out of time.

It depends on a middle-end patch adding a type-generic __builtin_iseqsig(), which I posted for review at: https://gcc.gnu.org/pipermail/gcc-patches/2023-June/620801.html

Bootstrapped and regtested on x86_64-pc-linux-gnu, OK to commit (once the middle-end patch is accepted)?

FX