https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100855
kargl at gcc dot gnu.org changed: What |Removed |Added ---------------------------------------------------------------------------- Priority|P3 |P4 Last reconfirmed| |2021-06-01 Ever confirmed|0 |1 Status|UNCONFIRMED |WAITING CC| |kargl at gcc dot gnu.org --- Comment #1 from kargl at gcc dot gnu.org --- This is not a gfortran bug. Adding code to use exp() and log(), I compiled the modified code: s0 = s0 + i**(0.05 + n) s1 = s1 + exp(0.05 + n) s2 = s2 + log(0.05 + n) with the -fdump-tree-optimized option. Looking at the dumped info, one finds the three lines _107 = __builtin_powf (_103, _106); _109 = __builtin_expf (_105); _111 = __builtin_logf (_105); If I compile the code with "-S -O3" and look at the assembly code I see call powf call expf call logf which are math functions contained in your system's libm. So, this is an issue with your libm not gfortran. I'll let someone else judge whether the bug should be closed with INVALID or WONTFIX.