[Bug target/124021] Interrupt function may clobber vstart on riscv

[law at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124021

--- Comment #7 from Jeffrey A. Law <law at gcc dot gnu.org> ---
No meaningful progress.  On a scale of 1-10, this is definitely much closer to
a 1 in terms of severity.  I don't think anyone has stumbled over it in
practice (it was initially raised by Ventana's DV team).

Patches would certainly be welcome as I don't forsee getting time to dive into
this anytime soon.