[Bug target/94986] missing diagnostic on ARM thumb2 compilation with -pg when using r7 in inline asm

[nsz at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94986

nsz at gcc dot gnu.org changed:

           What    |Removed                     |Added
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                 CC|                            |nsz at gcc dot gnu.org

--- Comment #2 from nsz at gcc dot gnu.org ---
on arm the -pg abi is

func:
  push {lr}
  bl _gnu_mcount_nc
  ...

so no frame pointer is involved, -pg implying
-fno-omit-frame-pointer is a historical mistake i think
(because some targets required fp for -pg, but most don't).

ideally r7 clobber would just work with -pg -fomit-frame-pointer.
the alloca problem is a separate issue (that r7 clobber may not
work with alloca).