Hi Thomas, Another glitch: the following test (reduced from gfortran.dg/optional_absent_4.f90)
module z implicit none contains subroutine findloc_4 (input, val, res, mask) logical, intent(in), optional :: mask(:,:) integer, intent(in) :: input(:,:) integer, dimension(:), intent(out) :: res integer, intent(in) :: val integer :: n = 1 res = findloc(input, val, dim=n) end subroutine findloc_4 end module z program main use z implicit none integer :: i2(2,3) = reshape([1,2,4,8,16,32], [2,3]) integer, dimension(3) :: res3 res3 = -2 call findloc_4 (i2, 4, res3) end program main gives at runtime a.out(77719,0x10335e5c0) malloc: Incorrect checksum for freed object 0x7fb131403d50: probably modified after being freed. Corrupt value: 0x0 a.out(77719,0x10335e5c0) malloc: *** set a breakpoint in malloc_error_break to debug Program received signal SIGABRT: Process abort signal. TIA, Dominique