[Bug fortran/95877] New: gfortran.dg/pr95689.f90

[Bug fortran/95877] New: gfortran.dg/pr95689.f90

[seurer at linux dot vnet.ibm.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95877

            Bug ID: 95877
           Summary: gfortran.dg/pr95689.f90
           Product: gcc
           Version: 9.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: seurer at linux dot vnet.ibm.com
  Target Milestone: ---

g:84323d9fa7526496d844f167f6353e0ec12279e8, r9-8693 

This same error occurs on both gcc 8 and 9.  Bad backport maybe?

commit 84323d9fa7526496d844f167f6353e0ec12279e8
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Sat Jun 20 16:09:45 2020 +0200

    PR fortran/95689 - ICE in check_sym_interfaces, at fortran/interface.c:2015

    With submodules, name mangling of interfaces may result in long internal
    symbols overflowing an internal buffer.  We now check that we do not
    exceed the enlarged buffer size.

    gcc/fortran/
        PR fortran/95689
        * interface.c (check_sym_interfaces): Enlarge temporary buffer,
        and add check on length on mangled name to prevent overflow.

    (cherry picked from commit 62c0c0ea7bfb6f8f6b8d767b05120cafb6823da6)


Executing on host:
/home/seurer/gcc/git/build/gcc-9-test/gcc/testsuite/gfortran/../../gfortran
-B/home/seurer/gcc/git/build/gcc-9-test/gcc/testsuite/gfortran/../../
-B/home/seurer/gcc/git/build/gcc-9-test/powerpc64-unknown-linux-gnu/./libgfortran/
/home/seurer/gcc/git/gcc-9-test/gcc/testsuite/gfortran.dg/pr95689.f90   
-fno-diagnostics-show-caret -fno-diagnostics-show-line-numbers
-fdiagnostics-color=never    -O  -fsecond-underscore -S -o pr95689.s   
(timeout = 300)
spawn -ignore SIGHUP
/home/seurer/gcc/git/build/gcc-9-test/gcc/testsuite/gfortran/../../gfortran
-B/home/seurer/gcc/git/build/gcc-9-test/gcc/testsuite/gfortran/../../
-B/home/seurer/gcc/git/build/gcc-9-test/powerpc64-unknown-linux-gnu/./libgfortran/
/home/seurer/gcc/git/gcc-9-test/gcc/testsuite/gfortran.dg/pr95689.f90
-fno-diagnostics-show-caret -fno-diagnostics-show-line-numbers
-fdiagnostics-color=never -O -fsecond-underscore -S -o pr95689.s
f951: internal compiler error: Segmentation fault
0x1090cd5b crash_signal
        /home/seurer/gcc/git/gcc-9-test/gcc/toplev.c:326
gfortran: internal compiler error: Segmentation fault signal terminated program
f951

Unfortunately the traceback in gdb isn't much help:

Program received signal SIGSEGV, Segmentation fault.
0x3930313233343534 in ?? ()
(gdb) where
#0  0x3930313233343534 in ?? ()
#1  0x3930313233343536 in ?? ()
Cannot access memory at address 0x3334353637383940

[Bug fortran/95877] [9 regression] ICE in test case gfortran.dg/pr95689.f90 after r9-8693

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95877

--- Comment #1 from anlauf at gcc dot gnu.org ---
(In reply to Bill Seurer from comment #0)
> g:84323d9fa7526496d844f167f6353e0ec12279e8, r9-8693 
> 
> This same error occurs on both gcc 8 and 9.  Bad backport maybe?

I do not get this error on x86_64-pc-linux-gnu, but we've seen this
before.

The backport was for a sort of borderline technical regression.
The fix is most likely contained in related patches that did not
backport straighforwardly.

I'd rather revert the commit on 8/9.

[Bug fortran/95877] [9 regression] ICE in test case gfortran.dg/pr95689.f90 after r9-8693

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95877

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2020-06-25
                 CC|                            |marxin at gcc dot gnu.org
             Status|UNCONFIRMED                 |NEW

[Bug fortran/95877] [8/9 regression] ICE in test case gfortran.dg/pr95689.f90 after r9-8693

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95877

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |8.5
            Summary|[9 regression] ICE in test  |[8/9 regression] ICE in
                   |case                        |test case
                   |gfortran.dg/pr95689.f90     |gfortran.dg/pr95689.f90
                   |after r9-8693               |after r9-8693

[Bug fortran/95877] [8/9 regression] ICE in test case gfortran.dg/pr95689.f90 after r9-8693

[anlauf at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95877

anlauf at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |WAITING

--- Comment #2 from anlauf at gcc dot gnu.org ---
The backport was reverted on 8- and 9-branch, since not a critical regression,
and a clean backport would need a manual backport of a series of other fixes.

The error should be gone now.  If you have confirmed this, please close
this PR.

[Bug fortran/95877] [8/9 regression] ICE in test case gfortran.dg/pr95689.f90 after r9-8693

[seurer at linux dot vnet.ibm.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95877

Bill Seurer <seurer at linux dot vnet.ibm.com> changed:

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

--- Comment #3 from Bill Seurer <seurer at linux dot vnet.ibm.com> ---
Yup.  I saw them succeed on a round of testing this morning.