[Bug c++/113957] New: [14 Regression] bad-mapper-1.C hangs on all Darwin.

[Bug c++/113957] New: [14 Regression] bad-mapper-1.C hangs on all Darwin.

[iains at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113957

            Bug ID: 113957
           Summary: [14 Regression] bad-mapper-1.C hangs on all Darwin.
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: iains at gcc dot gnu.org
          Reporter: iains at gcc dot gnu.org
  Target Milestone: ---
            Target: *-*-darwin*

Initial analysis: this seems to be hanging in a read in libcody.

[Bug c++/113957] [14 Regression] bad-mapper-1.C hangs on all Darwin.

[iains at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113957

Iain Sandoe <iains at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |14.0
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2024-02-16

[Bug c++/113957] [14 Regression] bad-mapper-1.C hangs on all Darwin.

[iains at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113957

--- Comment #1 from Iain Sandoe <iains at gcc dot gnu.org> ---
the problem is that liberty is using the value set by posix_spawnp for pid.
but:

(darwin):
     The argument pid is a pointer to a pid_t variable to receive the pid of
the spawned process; if this is NULL, then the pid of the spawned process is
not returned.  If this pointer is non-NULL, then on
     successful completion, the variable will be modified to contain the pid of
the spawned process.  The value is undefined in the case of a failure.

(linux):
Upon successful completion, posix_spawn() and posix_spawnp() place the PID of
the child process in pid, and return 0.  If there is an error during the fork()
step, then no child is created, the contents of *pid are
       unspecified, and these functions return an error number as described
below.

So .. I think the fix will be to set pid = -1 in the error paths .. will try
that.

[Bug other/113957] [14 Regression] bad-mapper-1.C hangs on all Darwin.

[iains at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113957

Iain Sandoe <iains at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|c++                         |other
           Keywords|wrong-code                  |error-recovery
                URL|                            |https://gcc.gnu.org/piperma
                   |                            |il/gcc-patches/2024-Februar
                   |                            |y/645814.html

--- Comment #2 from Iain Sandoe <iains at gcc dot gnu.org> ---
patch posted.

[Bug other/113957] [14 Regression] bad-mapper-1.C hangs on all Darwin.

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113957

--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Iain D Sandoe <iains@gcc.gnu.org>:

https://gcc.gnu.org/g:20e57660e64eab7c9ef0f2dd25f3088835f8f44f

commit r14-9072-g20e57660e64eab7c9ef0f2dd25f3088835f8f44f
Author: Iain Sandoe <iain@sandoe.co.uk>
Date:   Fri Feb 16 14:42:53 2024 +0000

    libiberty: Fix error return value in pex_unix_exec_child [PR113957].

    r14-5310-g879cf9ff45d940 introduced some new handling for spawning sub
    processes.  The return value from the generic exec_child is examined
    and needs to be < 0 to signal an error. However, the unix flavour of
    this routine is returning the PID value set from the posix_spawn{p}.

    This latter value is undefined per the manual pages for both Darwin
    and Linux, and it seems Darwin, at least, sets the value to some
    usually positive number (presumably the PID that would have been used
    if the fork had succeeded).

    The fix proposed here is to set the pid = -1 in the relevant error
    paths.

            PR other/113957

    libiberty/ChangeLog:

            * pex-unix.c (pex_unix_exec_child): Set pid = -1 in the error
            paths, since that is used to signal an erroneous outcome for
            the routine.

    Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>

[Bug other/113957] [14 Regression] bad-mapper-1.C hangs on all Darwin.

[iains at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113957

Iain Sandoe <iains at gcc dot gnu.org> changed:

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

--- Comment #4 from Iain Sandoe <iains at gcc dot gnu.org> ---
fixed on trunk.