https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78549
--- Comment #15 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> --- For my own baseline: gcc6: real 0m6.948s gcc7: real 0m9.906s gcc8: real 0m10.415s I backported removal of the caching mentioned in comment #14 to gcc7. The two should be identical except that gcc7 is a released branch. IIRC released branches have debugging code removed. I do not know if this accounts for the difference between gcc7 and gcc8.