Unexpected "Program Exception - access violation" error during runtime with allocatable objects

FortranFan · ‎03-11-2017

The following code does some 'voodoo' using a C pointer, TRANSFER intrinsic, and what not, but it is standard-conforming as far as I can tell. It functions as expected when compiled using gfortran, however it runs into a program exception with Intel Fortran compiler. Note the exception arises with objects of ALLOCATABLE attribute; if line 7 is commented out and line 8 is uncommented in the main program, it works ok with Intel Fortran compiler and so it does with gfortran.

module m

   use, intrinsic :: iso_c_binding, only : c_loc, c_ptr, c_f_pointer

   implicit none

   private

   public :: get_s

   character(len=*), parameter :: s = "Hello World!"

contains

   subroutine get_s( t, t_size )

      type(*), intent(inout), target :: t(..)
      integer, intent(in)            :: t_size

      blk: block

         character(len=t_size), pointer :: ptr_s => null()

         call c_f_pointer( cptr=c_loc(t), fptr=ptr_s )

         ptr_s = transfer( source=s, mold=ptr_s )

         ptr_s => null()

      end block blk

      return

   end subroutine get_s

end module m

program p

   use m, only : get_s

   integer, parameter :: lens = 12

   character(len=:), allocatable :: s
   !character(len=lens) :: s

   s = repeat( " ", ncopies=lens )
   call get_s( s, len(s) )
   print *, "s = ", s

   stop

end program p

C:\..>ifort /c /standard-semantics /traceback /warn:all /check:all m.f90
Intel(R) Visual Fortran Intel(R) 64 Compiler for applications running on Intel(R
) 64, Version 17.0.1.143 Build 20161005
Copyright (C) 1985-2016 Intel Corporation.  All rights reserved.


C:\..>ifort /c /standard-semantics /traceback /warn:all /check:all p.f90
Intel(R) Visual Fortran Intel(R) 64 Compiler for applications running on Intel(R
) 64, Version 17.0.1.143 Build 20161005
Copyright (C) 1985-2016 Intel Corporation.  All rights reserved.


C:\..>link /out:p.exe /subsystem:console p.obj m.obj
Microsoft (R) Incremental Linker Version 14.00.24215.1
Copyright (C) Microsoft Corporation.  All rights reserved.


C:\..>p.exe
 s =
forrtl: severe (157): Program Exception - access violation
Image              PC                Routine            Line        Source

p.exe              000000013FC46DE0  Unknown               Unknown  Unknown
p.exe              000000013FC097C7  Unknown               Unknown  Unknown
p.exe              000000013FC0143A  MAIN__                     12  p.f90
p.exe              000000013FC4F3CE  Unknown               Unknown  Unknown
p.exe              000000013FC4FD5D  Unknown               Unknown  Unknown
kernel32.dll       0000000076E159CD  Unknown               Unknown  Unknown
ntdll.dll          000000007704A561  Unknown               Unknown  Unknown

P.S.> a typo (change use s_m to use m) in main program p corrected per Message #2

andrew_4619 · ‎03-12-2017

For what it is worth that fails on 17 update 2 also, I suspect FF has not been "brave" enough to install that. There is a typo on the reproducer the module name I changed to s_m to match the use name.

C:\Users\Andrew\Desktop\fft>ifort /c /standard-semantics /traceback /warn:all /check:all m.f90
Intel(R) Visual Fortran Intel(R) 64 Compiler for applications running on Intel(R) 64, Version 17.0.2.187 Build 20170213
Copyright (C) 1985-2017 Intel Corporation.  All rights reserved.

C:\Users\Andrew\Desktop\fft>ifort /c /standard-semantics /traceback /warn:all /check:all p.f90
Intel(R) Visual Fortran Intel(R) 64 Compiler for applications running on Intel(R) 64, Version 17.0.2.187 Build 20170213
Copyright (C) 1985-2017 Intel Corporation.  All rights reserved.

C:\Users\Andrew\Desktop\fft>link /out:p.exe /subsystem:console p.obj m.obj
Microsoft (R) Incremental Linker Version 12.00.40629.0
Copyright (C) Microsoft Corporation.  All rights reserved.

C:\Users\Andrew\Desktop\fft>p
 s =
forrtl: severe (157): Program Exception - access violation
Image              PC                Routine            Line        Source
p.exe              00007FF643BE60D9  Unknown               Unknown  Unknown
p.exe              00007FF643BA9F47  Unknown               Unknown  Unknown
p.exe              00007FF643BA143A  MAIN__                     12  p.f90
p.exe              00007FF643BEFC0E  Unknown               Unknown  Unknown
p.exe              00007FF643BF0A50  Unknown               Unknown  Unknown
KERNEL32.DLL       00007FFC93F08364  Unknown               Unknown  Unknown
ntdll.dll          00007FFC94CE70D1  Unknown               Unknown  Unknown

FortranFan · ‎03-12-2017

andrew_4619 wrote:

For what it is worth that fails on 17 update 2 also, I suspect FF has not been "brave" enough to install that. There is a typo on the reproducer the module name I changed to s_m to match the use name. ..

Thanks much and a great catch on the typo, indeed I have not tried Update 2. If it's not too much trouble, can you please check whether a modified main, where line 7 is commented out and line 8 is uncommented, works with Update 2?

andrew_4619 · ‎03-12-2017

FortranFan wrote:
If it's not too much trouble, can you please check whether a modified main, where line 7 is commented out and line 8 is uncommented, works with Update 2?

Yes that works OK.

FortranFan · ‎03-12-2017

Thanks Andrew that's good to know.

Kevin_D_Intel · ‎03-12-2017

Thank you for reporting this. I reported it to Development.

(Internal tracking id: DPD200418831)