[Bug fortran/103258] New: [12 Regression] ICE in gfc_typenode_for_spec, at fortran/trans-types.c:1114

[Bug fortran/103258] New: [12 Regression] ICE in gfc_typenode_for_spec, at fortran/trans-types.c:1114

[gscfq@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103258

            Bug ID: 103258
           Summary: [12 Regression] ICE in gfc_typenode_for_spec, at
                    fortran/trans-types.c:1114
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gscfq@t-online.de
  Target Milestone: ---

This changed between 20211031 and 20211107 :


$ cat z1.f90
subroutine s(n)
implicit none
character(n+m) :: c
entry e(m)
end


$ gfortran-12-20211031 -c z1.f90
z1.f90:1:14:

    1 | subroutine s(n)
      |              1
Error: Symbol 'n' at (1) has no IMPLICIT type


$ gfortran-12-20211114 -c z1.f90
z1.f90:1:12:

    1 | subroutine s(n)
      |            1
internal compiler error: in gfc_typenode_for_spec, at
fortran/trans-types.c:1114
0x8d7590 gfc_typenode_for_spec(gfc_typespec*, int)
        ../../gcc/fortran/trans-types.c:1114
0x8d7796 gfc_sym_type(gfc_symbol*, bool)
        ../../gcc/fortran/trans-types.c:2272
0x8d5c6f gfc_get_function_type(gfc_symbol*, gfc_actual_arglist*, char const*)
        ../../gcc/fortran/trans-types.c:3126
0x86aa04 build_function_decl
        ../../gcc/fortran/trans-decl.c:2390
0x872976 gfc_create_function_decl(gfc_namespace*, bool)
        ../../gcc/fortran/trans-decl.c:3099
0x878fee gfc_generate_function_code(gfc_namespace*)
        ../../gcc/fortran/trans-decl.c:7461
0x7fb32e translate_all_program_units
        ../../gcc/fortran/parse.c:6638
0x7fb32e gfc_parse_file()
        ../../gcc/fortran/parse.c:6925
0x84806f gfc_be_parse_file
        ../../gcc/fortran/f95-lang.c:216

[Bug fortran/103258] [12 Regression] ICE in gfc_typenode_for_spec, at fortran/trans-types.c:1114 since r12-4979-gee11be7f2d788e60

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103258

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |marxin at gcc dot gnu.org,
                   |                            |sandra at codesourcery dot com
            Summary|[12 Regression] ICE in      |[12 Regression] ICE in
                   |gfc_typenode_for_spec, at   |gfc_typenode_for_spec, at
                   |fortran/trans-types.c:1114  |fortran/trans-types.c:1114
                   |                            |since
                   |                            |r12-4979-gee11be7f2d788e60
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2021-11-16
     Ever confirmed|0                           |1

--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
Started with r12-4979-gee11be7f2d788e60.

[Bug fortran/103258] [12 Regression] ICE in gfc_typenode_for_spec, at fortran/trans-types.c:1114 since r12-4979-gee11be7f2d788e60

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103258

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |12.0
           Priority|P3                          |P4

[Bug fortran/103258] [12 Regression] ICE in gfc_typenode_for_spec, at fortran/trans-types.c:1114 since r12-4979-gee11be7f2d788e60

[sandra at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103258

sandra at gcc dot gnu.org changed:

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

--- Comment #2 from sandra at gcc dot gnu.org ---
I'll take a look when I have time, but I'm deep in another bug right now so it
may be a few days.  Anybody else feel free to grab it meanwhile...

[Bug fortran/103258] [12 Regression] ICE in gfc_typenode_for_spec, at fortran/trans-types.c:1114 since r12-4979-gee11be7f2d788e60

[sandra at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103258

--- Comment #3 from sandra at gcc dot gnu.org ---
This looks like an existing bug in error checking that was exposed by my patch
to do...  more error checking.  :-S

The problem is that gfc_set_default_type in symbol.c is setting
sym->attr.untyped even when errors are suppressed or buffered and discarded
during parsing.  Since it's marked as having already been diagnosed, we aren't
giving an error in subsequent calls where errors are *not* being suppressed or
discarded, and thus compilation continues as if nothing were wrong, until it
falls over.

Previously we were resolving only the second operand "m" in the "(n+m)"
expression in a situation where errors are buffered in the parsing stage,
leaving "n" without the attr.untyped flag set so that it was being diagnosed
later during the actual resolve phase of processing.  Now it is setting that
flag on both "n" and "m" so neither ever gives a real error.

I've got a hacky patch to avoid setting sym->attr.untyped when a real error
might not be given, but I'm not sure if it's the right solution.  Maybe a
better solution would be to emit the diagnostic somewhere other than
gfc_set_default_type, at a known point in the processing where it'll only
happen once?

[Bug fortran/103258] [12 Regression] ICE in gfc_typenode_for_spec, at fortran/trans-types.c:1114 since r12-4979-gee11be7f2d788e60

[sandra at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103258

--- Comment #4 from sandra at gcc dot gnu.org ---
Created attachment 51980
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=51980&action=edit
hacky patch

Attached patch has not been regression tested, but it does seem to fix the
original testcase, which now produces:

$ gfortran -c pr103258.f90
pr103258.f90:3:13:

    3 | character(n+m) :: c
      |             1
Error: Symbol 'm' at (1) has no IMPLICIT type
pr103258.f90:1:14:

    1 | subroutine s(n)
      |              1
Error: Symbol 'n' at (1) has no IMPLICIT type

[Bug fortran/103258] [12 Regression] ICE in gfc_typenode_for_spec, at fortran/trans-types.c:1114 since r12-4979-gee11be7f2d788e60

[sandra at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103258

--- Comment #5 from sandra at gcc dot gnu.org ---
The previous hacky patch had some testsuite regressions.  I've posted a less
hacky one that doesn't trigger new failures here:

https://gcc.gnu.org/pipermail/gcc-patches/2022-January/587632.html

[Bug fortran/103258] [12 Regression] ICE in gfc_typenode_for_spec, at fortran/trans-types.c:1114 since r12-4979-gee11be7f2d788e60

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103258

--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Sandra Loosemore <sandra@gcc.gnu.org>:

https://gcc.gnu.org/g:85a3442c85aedb00c59e986f16cccbb8ec60d777

commit r12-6268-g85a3442c85aedb00c59e986f16cccbb8ec60d777
Author: Sandra Loosemore <sandra@codesourcery.com>
Date:   Tue Jan 4 18:18:13 2022 -0800

    Fortran: Fix ICE caused by missing error for untyped symbol [PR103258]

    The bit on a symbol to mark that it had already been diagnosed as
    lacking a type was getting set even when the error was suppressed or
    discarded, specifically when doing early resolution on a character
    length expression to see if it can be constant-folded.  Explicitly
    suppress errors before doing that, then check whether they are
    suppressed before setting the bit.

    2022-01-04  Sandra Loosemore  <sandra@codesourcery.com>

            PR fortran/103258

            gcc/fortran/
            * decl.c (gfc_match_char_spec): Suppress errors around call
            to gfc_reduce_init_expr.
            * error.c (gfc_query_suppress_errors): New.
            * gfortran.h (gfc_query_suppress_errors): Declare.
            * symbol.c (gfc_set_default_type): Check gfc_query_suppress_errors.

            gcc/testsuite/
            * gfortran.dg/pr103258.f90: New.

[Bug fortran/103258] [12 Regression] ICE in gfc_typenode_for_spec, at fortran/trans-types.c:1114 since r12-4979-gee11be7f2d788e60

[sandra at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103258

sandra at gcc dot gnu.org changed:

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

--- Comment #7 from sandra at gcc dot gnu.org ---
Should be fixed now.