[Bug target/108532] New: march used on the object but mcpu conflicts still produces an warning with LTO

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108532

            Bug ID: 108532
           Summary: march used on the object but mcpu conflicts still
                    produces an warning with LTO
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Keywords: diagnostic, lto
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---
            Target: aarch64-linux-gnu

cat t.c
int main(void) {}

~/upstream-gcc/bin/gcc -c -flto -march=armv8.4-a t.c
~/upstream-gcc/bin/gcc t.o -flto -mcpu=generic
lto1: warning: switch ‘-mcpu=generic’ conflicts with ‘-march=armv8.4-a’ switch
lto1: warning: switch ‘-mcpu=generic’ conflicts with ‘-march=armv8.4-a’ switch


This is wrong.
gcc version 13.0.0 20220808 (experimental)