[Bug fortran/114023] New: complex part%ref of complex named constant array cannot be used in an initialization expression.

[Bug fortran/114023] New: complex part%ref of complex named constant array cannot be used in an initialization expression.

[kargl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114023

            Bug ID: 114023
           Summary: complex part%ref of complex named constant array
                    cannot be used in an initialization expression.
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: kargl at gcc dot gnu.org
  Target Milestone: ---

Found with the Fujitsu testsuite.  The original code led to
an ICE, but the modified version here compiles and executes.
It is however wrong-code as the testcase stops at STOP 1.

!
! https://github.com/fujitsu/compiler-test-suite
! Modified from Fortran/0093/0093_0025.f90
!
   complex(kind=8),  parameter :: cmp1(3) = [(1,2),(3,4),(5,6)]
   complex(kind=16), parameter :: cmp2(3) = [(1,2),(3,4),(5,6)]

   real(8)  :: rr(3) = cmp1%re
   real(8)  :: qq(3) = cmp1%im
   real(16) :: rr2(3) = cmp2%re
   real(16) :: qq2(3) = cmp2%im

   if (any(int(rr)  /= [1,3,5])) stop 1
   if (any(int(qq)  /= [2,4,6])) stop 2
   if (any(int(rr2) /= [1,3,5])) stop 3
   if (any(int(qq2) /= [2,4,6])) stop 4

end

Modifying the code to output rr shows
% gfcx -o z 0093/0093_0036.f90 && ./z
   1.0000000000000000        2.0000000000000000        0.0000000000000000

[Bug fortran/114023] complex part%ref of complex named constant array cannot be used in an initialization expression.

[kargl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114023

kargl at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P4

--- Comment #1 from kargl at gcc dot gnu.org ---
This one is a bit uglier.  For the testcase,


program foo

   implicit none

   complex(kind=8), parameter :: cmp1(3) = [(1,2),(3,4),(5,6)]

   real :: rr(3) = cmp1%re

   if (any(int(rr) /= [1,3,5])) then
      print '(3(F4.1))', rr
      stop 1
   end if

end

one gets an ICE

% gfcx -o z a.f90 && ./z
a.f90:5:11:

    5 | program foo
      |           1
internal compiler error: in gfc_conv_array_initializer, at
fortran/trans-array.cc:6662
0x6eb2cf gfc_conv_array_initializer(tree_node*, gfc_expr*)
        ../../gccx/gcc/fortran/trans-array.cc:6662

This caused by the insertion of a conversion function __convert_r8_r4()
into the initializer where gfc_conv_array_initializer() is not prepared
to hand it.  Now, if the type declaration of rr is changed to 'real(8)',
then a conversion function is not inserted but wrong code is generated.
I suspect that we need to go code spelunking in resolve.cc.

[Bug fortran/114023] complex part%ref of complex named constant array cannot be used in an initialization expression.

[jvdelisle at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114023

Jerry DeLisle <jvdelisle at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2024-03-13

--- Comment #2 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> ---
Steve, Anuj is interested in digging in on this one. This will be a learning
experience.

[Bug fortran/114023] complex part%ref of complex named constant array cannot be used in an initialization expression.

[sgk at troutmask dot apl.washington.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114023

--- Comment #3 from Steve Kargl <sgk at troutmask dot apl.washington.edu> ---
On Wed, Mar 13, 2024 at 06:02:58PM +0000, jvdelisle at gcc dot gnu.org wrote:
> 
> --- Comment #2 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> ---
> Steve, Anuj is interested in digging in on this one. This will be a learning
> experience.
> 

That's fine with.  If Anuj or you have questions or
want me to look at something, just ping me.