gcc/testsuite/gfortran.dg/short_circuiting.f90

   1 ! { dg-do compile }
   2 ! { dg-additional-options "-Wextra" }
   3 !
   4 ! PR 85599: warn about short-circuiting of logical expressions for non-pure functions
   5 !
   6 ! Contributed by Janus Weil <janus@gcc.gnu.org>
   7
   8 module a
   9
  10    interface impl_pure_a
  11       module procedure impl_pure_a1
  12    end interface
  13
  14 contains
  15
  16     logical function impl_pure_a1()
  17       impl_pure_a1 = .true.
  18    end function
  19
  20 end module
  21
  22
  23 program short_circuit
  24
  25    use a
  26
  27    logical :: flag
  28    flag = .false.
  29    flag = check() .and. flag
  30    flag = flag .and. check()        ! { dg-warning "might not be evaluated" }
  31    flag = flag .and. pure_check()
  32    flag = flag .and. impl_pure_1()
  33    flag = flag .and. impl_pure_2()
  34    flag = flag .and. impl_pure_a1()
  35    flag = flag .and. impl_pure_a()
  36
  37 contains
  38
  39    logical function check()
  40       integer, save :: i = 1
  41       print *, "check", i
  42       i = i + 1
  43       check = .true.
  44    end function
  45
  46    logical pure function pure_check()
  47       pure_check = .true.
  48    end function
  49
  50    logical function impl_pure_1()
  51       impl_pure_1 = .true.
  52    end function
  53
  54    logical function impl_pure_2()
  55       impl_pure_2 = impl_pure_1()
  56    end function
  57
  58
  59 end