[Bug rtl-optimization/97295] ICE on firefox built with lto+pgo: dist/include/mozilla/Casting.h:64:1: internal compiler error: in to_frequency, at profile-count.c:273

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97295

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |ASSIGNED

--- Comment #5 from Martin Liška <marxin at gcc dot gnu.org> ---
So it's pretty clear what happens, it's about mixing of different flags:

TestFloatingPoint.o:

'-fno-openmp' '-fno-openacc' '-mtune=generic' '-march=x86-64' '-O3' '-O0'
'-Wno-error=maybe-uninitialized' '-Wno-error=deprecated-declarations'
'-Wno-error=array-bounds' '-Wno-error=coverage-mismatch'
'-Wno-error=free-nonheap-object' '-Wno-error=class-memaccess'
'-Wno-error=deprecated-copy' '-Wno-error=shadow' '-flto' '-flifetime-dse=1'
'-fstack-protector-strong' '-fPIC' '-fno-strict-aliasing' '-ffunction-sections'
'-fdata-sections' '-fno-exceptions' '-fno-math-errno' '-fomit-frame-pointer'
'-funwind-tables'

while Unified_cpp_mfbt0.o:

'-fno-openmp' '-fno-openacc' '-mtune=generic' '-march=x86-64' '-O3'
'-Wno-error=maybe-uninitialized' '-Wno-error=deprecated-declarations'
'-Wno-error=array-bounds' '-Wno-error=coverage-mismatch'
'-Wno-error=free-nonheap-object' '-Wno-error=class-memaccess'
'-Wno-error=deprecated-copy' '-flto' '-flifetime-dse=1'
'-fstack-protector-strong' '-fPIC' '-fno-strict-aliasing' '-ffunction-sections'
'-fdata-sections' '-fno-exceptions' '-fno-math-errno' '-fomit-frame-pointer'
'-funwind-tables' '-fprofile-use' '-fprofile-correction'

the profiles are merged in ipa_merge_profiles where match=false due to a
different CFG and we forget to drop back dst->count. I'll prepare a patch for
it.