https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112661
--- Comment #1 from Robin Dapp <rdapp at gcc dot gnu.org> --- Confirmed, smaller example: program main implicit none integer, parameter :: n=5 character(len=6), dimension(n,n) :: a character(len=6), dimension(n) :: r1 integer :: i logical, dimension(n,n) :: mask write (unit=a,fmt='(I6.6)') (i*i+200-17*i,i=1,n*n) mask = .true. forall (i=1:n) mask(i,i) = .false. end forall r1 = maxval(a, dim=1, mask=mask) end program main compiled with -O3 -march=rv64gcv_zvl256b