Thanks. That provides pointers to the specific issues:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71345

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77430

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64767

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77444

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And fixes have also started coming in:

https://gcc.gnu.org/viewcvs?rev=239959&root=gcc&view=rev

Kudos for investigating and reporting the issues.