https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110311
--- Comment #51 from Jakub Jelinek <jakub at gcc dot gnu.org> --- The easiest would be to bisect gcc in the suspected ranges, that way you'd know for sure which git commit introduced the problem and which fixed/"fixed" it. If it is about what the compiler emits, one doesn't have to build whole gcc from scratch each time, but can just --disable-bootstrap build it and during bisection whenever git is updated just ./config.status --recheck; ./config.status; make -jN in libcpp, libiberty and gcc subdirectories and use f951/gfortran binariers from that instead of the ones from the initial build to build your project.
