[Bug target/109456] `-ffixed-reg` cannot prevent using `reg` for ABI-mandated roles (argument register etc) and the behavior should be documented more clearly

[xry111 at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109456

Xi Ruoyao <xry111 at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|`-ffixed` is ignored for    |`-ffixed-reg` cannot
                   |`a` registers on RISC-V.    |prevent using `reg` for
                   |                            |ABI-mandated roles
                   |                            |(argument register etc) and
                   |                            |the behavior should be
                   |                            |documented more clearly

--- Comment #11 from Xi Ruoyao <xry111 at gcc dot gnu.org> ---
Not a RISCV-specific issue.