Comment # 3 on bug 1170849 from Fabian Vogt

(In reply to Dirk Mueller from comment #2)
> I think we should only autopatch files that look lik ethey're created from
> autotools.

It checks for "config-patches" first, which is part of

> # Please send patches to <config-patches@gnu.org>.

> the cargo package files are most likely not autotools ones?

It bundles libbacktrace sources.

It still does a unnecessary replacement here though, as aarch64 is supported by
this specific config.*. The missing riscv64- triggers it apparently.