[Bug fortran/114874] New: [14/15 Regression] ICE with select type, type is (character(*)), and substring

[Bug fortran/114874] New: [14/15 Regression] ICE with select type, type is (character(*)), and substring

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

            Bug ID: 114874
           Summary: [14/15 Regression] ICE with select type, type is
                    (character(*)), and substring
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: anlauf at gcc dot gnu.org
  Target Milestone: ---

The following code fails for me with latest 14-branch/15-release candidate:

program p
  implicit none
  class(*), allocatable :: c
  c = 'abc'
  select type (c)
  type is (character(*))
     print *, c
     print *, c(2:2)  ! ICE
  end select
end

 p __copy_character_1hhh.f90:8:22:

    8 |      print *, c(2:2)  ! ICE
      |                      1
internal compiler error: Segmentation fault
0x10c6f6f crash_signal
        ../../gcc-14/gcc/toplev.cc:319
0xa7e6f1 gfc_conv_scalarized_array_ref
        ../../gcc-14/gcc/fortran/trans-array.cc:3938
0xa7f596 gfc_conv_array_ref(gfc_se*, gfc_array_ref*, gfc_expr*, locus*)
        ../../gcc-14/gcc/fortran/trans-array.cc:4094
0xac25ea gfc_conv_variable
        ../../gcc-14/gcc/fortran/trans-expr.cc:3181
0xac5be2 gfc_conv_expr_reference(gfc_se*, gfc_expr*)
        ../../gcc-14/gcc/fortran/trans-expr.cc:9935
0xaf00b6 gfc_trans_transfer(gfc_code*)
        ../../gcc-14/gcc/fortran/trans-io.cc:2609
0xa73157 trans_code
        ../../gcc-14/gcc/fortran/trans.cc:2583
0xaed036 build_dt
        ../../gcc-14/gcc/fortran/trans-io.cc:2053
0xa73177 trans_code
        ../../gcc-14/gcc/fortran/trans.cc:2555
0xb1471f gfc_trans_block_construct(gfc_code*)
        ../../gcc-14/gcc/fortran/trans-stmt.cc:2377
0xa73337 trans_code
        ../../gcc-14/gcc/fortran/trans.cc:2459
0xb0abf7 gfc_trans_select_type_cases
        ../../gcc-14/gcc/fortran/trans-stmt.cc:3020
0xb15ff4 gfc_trans_select_type(gfc_code*)
        ../../gcc-14/gcc/fortran/trans-stmt.cc:3729
0xa730a7 trans_code
        ../../gcc-14/gcc/fortran/trans.cc:2479
0xb1471f gfc_trans_block_construct(gfc_code*)
        ../../gcc-14/gcc/fortran/trans-stmt.cc:2377
0xa73337 trans_code
        ../../gcc-14/gcc/fortran/trans.cc:2459
0xaa8ed1 gfc_generate_function_code(gfc_namespace*)
        ../../gcc-14/gcc/fortran/trans-decl.cc:7880
0xa1b65f translate_all_program_units
        ../../gcc-14/gcc/fortran/parse.cc:7099
0xa1b65f gfc_parse_file()
        ../../gcc-14/gcc/fortran/parse.cc:7413
0xa6fe7f gfc_be_parse_file
        ../../gcc-14/gcc/fortran/f95-lang.cc:241

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

anlauf at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|                            |10.5.0, 11.4.1, 12.3.1,
                   |                            |13.2.1
           Keywords|                            |ice-on-valid-code
           Priority|P3                          |P4

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

--- Comment #1 from anlauf at gcc dot gnu.org ---
(In reply to anlauf from comment #0)
> The following code fails for me with latest 14-branch/15-release candidate:

Oops, I meant: 14-release candidate/15-mainline after branching...

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

--- Comment #2 from anlauf at gcc dot gnu.org ---
The dump-fortran-original shows the following difference between 13 and 14:

@@ -58,7 +58,7 @@
   code:
   ASSIGN p:c 'abc'

-  BLOCK 
+  SELECT TYPE 
     symtree: '__tmp_CHARACTER_0_1'|| symbol: '__tmp_CHARACTER_0_1' 
       type spec : (CHARACTER () 1)
       attributes: (VARIABLE  SELECT-TYPE-TEMPORARY ASSOCIATE-VAR)
@@ -66,7 +66,7 @@
       type spec : (UNKNOWN 0)
       attributes: (LABEL )

-    SELECT TYPE _loc[((p:c % _vptr))]
+    SELECT CASE _loc[((p:c % _vptr))]
     CASE (_loc[((p:__vtab_CHARACTER_1_))] 85893463) 

     ASSOCIATE   = p:c % _data
@@ -74,11 +74,11 @@
         type spec : (UNKNOWN 0)
         attributes: (LABEL )
       WRITE UNIT=6 FMT=-1
-      TRANSFER block@1:__tmp_CHARACTER_0_1(2:2)
+      TRANSFER block@1:__tmp_CHARACTER_0_1(UNKNOWN)
       DT_END
     END ASSOCIATE 
     END SELECT
-  END BLOCK 
+  END SELECT TYPE 

 CONTAINS

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

anlauf at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pault at gcc dot gnu.org

--- Comment #3 from anlauf at gcc dot gnu.org ---
Adding Paul, hoping that he can tell what changed for SELECT TYPE recently.

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[pault at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

Paul Thomas <pault at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2024-04-29
             Status|UNCONFIRMED                 |NEW

--- Comment #4 from Paul Thomas <pault at gcc dot gnu.org> ---
(In reply to anlauf from comment #3)
> Adding Paul, hoping that he can tell what changed for SELECT TYPE recently.

Hmmm! Nothing that I am aware of. I'll take a look tomorrow, The changes are
most strange.

Why do I get that horrible feeling?

Paul

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[pault at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

--- Comment #5 from Paul Thomas <pault at gcc dot gnu.org> ---
(In reply to Paul Thomas from comment #4)
> (In reply to anlauf from comment #3)
> > Adding Paul, hoping that he can tell what changed for SELECT TYPE recently.
> 

When c is an array, it compiles and runs fine with mainline. The parse-tree
looks sensible too, unlike the scalar version.

program p
  implicit none
  class(*), allocatable :: c(:)
  c = ['abc']
  select type (c)
  type is (character(*))
     print *, c
     print *, c(1)(2:2)  ! Doesn't ICE
  end select
end

Paul

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |14.0

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[pault at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

--- Comment #6 from Paul Thomas <pault at gcc dot gnu.org> ---
(In reply to anlauf from comment #3)
> Adding Paul, hoping that he can tell what changed for SELECT TYPE recently.

Needless to say, the regression is caused by r14-9489.

I have a fix that regtests OK but causes a regression in an, as yet, untested
corner:

  subroutine foobar
    type :: t
      integer :: i
    end type
    class(*), allocatable :: c
    c = t (1)
    select type (c)
      type is (t)
        if (c(1)%i .ne. 1) stop 5 ! This now ICEs
    end select
  end

My efforts have been interrupted by a failure of make-install, which seems to
happen every few months. I rather think that I should go back to magnetic
drives, rather than SSD.

It will now have to wait until tomorrow.

Paul

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[pault at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

Paul Thomas <pault at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |pault at gcc dot gnu.org

--- Comment #7 from Paul Thomas <pault at gcc dot gnu.org> ---
Created attachment 58104
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58104&action=edit
Fix for this PR

This seems to be the best fix. I have tried several different approaches in the
last two days but it has been an uphill struggle against the state of the block
namespaces at this stage of the compilation.

I'll think about it for another day or so before submitting.

Cheers

Paul

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|14.0                        |14.2

--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 14.1 is being released, retargeting bugs to GCC 14.2.

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

--- Comment #9 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Paul Thomas <pault@gcc.gnu.org>:

https://gcc.gnu.org/g:5f5074fe7aaf9524defb265299a985eecba7f914

commit r15-633-g5f5074fe7aaf9524defb265299a985eecba7f914
Author: Paul Thomas <pault@gcc.gnu.org>
Date:   Fri May 17 15:19:26 2024 +0100

    Fortran: Fix select type regression due to r14-9489 [PR114874]

    2024-05-17  Paul Thomas  <pault@gcc.gnu.org>

    gcc/fortran
            PR fortran/114874
            * gfortran.h: Add 'assoc_name_inferred' to gfc_namespace.
            * match.cc (gfc_match_select_type): Set 'assoc_name_inferred'
            in select type namespace if the selector has inferred type.
            * primary.cc (gfc_match_varspec): If a select type temporary
            is apparently scalar and a left parenthesis has been detected,
            check the current namespace has 'assoc_name_inferred' set. If
            so, set inferred_type.
            * resolve.cc (resolve_variable): If the namespace of a select
            type temporary is marked with 'assoc_name_inferred' call
            gfc_fixup_inferred_type_refs to ensure references are OK.
            (gfc_fixup_inferred_type_refs): Catch invalid array refs..

    gcc/testsuite/
            PR fortran/114874
            * gfortran.dg/pr114874_1.f90: New test for valid code.
            * gfortran.dg/pr114874_2.f90: New test for invalid code.

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

--- Comment #10 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-14 branch has been updated by Paul Thomas <pault@gcc.gnu.org>:

https://gcc.gnu.org/g:c887341432bb71cf5540d54955ad7265b0aaca77

commit r14-10216-gc887341432bb71cf5540d54955ad7265b0aaca77
Author: Paul Thomas <pault@gcc.gnu.org>
Date:   Fri May 17 15:19:26 2024 +0100

    Fortran: Fix select type regression due to r14-9489 [PR114874]

    2024-05-17  Paul Thomas  <pault@gcc.gnu.org>

    gcc/fortran
            PR fortran/114874
            * gfortran.h: Add 'assoc_name_inferred' to gfc_namespace.
            * match.cc (gfc_match_select_type): Set 'assoc_name_inferred'
            in select type namespace if the selector has inferred type.
            * primary.cc (gfc_match_varspec): If a select type temporary
            is apparently scalar and a left parenthesis has been detected,
            check the current namespace has 'assoc_name_inferred' set. If
            so, set inferred_type.
            * resolve.cc (resolve_variable): If the namespace of a select
            type temporary is marked with 'assoc_name_inferred' call
            gfc_fixup_inferred_type_refs to ensure references are OK.
            (gfc_fixup_inferred_type_refs): Catch invalid array refs..

    gcc/testsuite/
            PR fortran/114874
            * gfortran.dg/pr114874_1.f90: New test for valid code.
            * gfortran.dg/pr114874_2.f90: New test for invalid code.

    (cherry picked from commit 5f5074fe7aaf9524defb265299a985eecba7f914)

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[pault at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

Paul Thomas <pault at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|NEW                         |RESOLVED

--- Comment #11 from Paul Thomas <pault at gcc dot gnu.org> ---
Hi Harald,

Your comments have been implemented and the patch committed to both affected
branches.

Thanks for the report and your help in honing up the fix.

Paul

[Bug fortran/114874] [14/15 Regression] ICE with select type, type is (character(*)), and substring

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114874

anlauf at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ryan.mulhall at noaa dot gov

--- Comment #12 from anlauf at gcc dot gnu.org ---
*** Bug 115193 has been marked as a duplicate of this bug. ***