https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110505
Bug ID: 110505
Summary: Memory Problems with Array Constructor From Zero Size
Allocatable Array Function Result
Product: gcc
Version: 13.1.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: everythingfunctional at protonmail dot com
Target Milestone: ---
The following program breaks valgrind. Note that the loop is actually required
and can't be manually unrolled or it doesn't exhibit the same behavior.
program example
integer :: i
do i = 1, 2
print *, [make_array(), make_array()]
end do
contains
function make_array()
integer, allocatable :: make_array(:)
allocate(make_array(0))
end function
end program
$ gfortran -g example.f90
$ valgrind ./a.out
==216962== Memcheck, a memory error detector
==216962== Copyright (C) 2002-2022, and GNU GPL'd, by Julian Seward et al.
==216962== Using Valgrind-3.21.0 and LibVEX; rerun with -h for copyright info
==216962== Command: ./a.out
==216962==
==216962== realloc() with size 0
==216962== at 0x4846BE0: realloc (vg_replace_malloc.c:1649)
==216962== by 0x10960F: MAIN__ (example.f90:4)
==216962== by 0x10976F: main (example.f90:3)
==216962== Address 0x4e68a30 is 0 bytes after a block of size 0 alloc'd
==216962== at 0x4846BE0: realloc (vg_replace_malloc.c:1649)
==216962== by 0x1094BD: MAIN__ (example.f90:4)
==216962== by 0x10976F: main (example.f90:3)
==216962==
Error:
unknown error code 14
Memcheck: the 'impossible' happened:
unknown error code in mc_eq_Error
host stacktrace:
==216962== at 0x58042CDA: show_sched_status_wrk (m_libcassert.c:406)
==216962== by 0x58042E07: report_and_quit (m_libcassert.c:477)
==216962== by 0x580430DF: panic (m_libcassert.c:553)
==216962== by 0x580430DF: vgPlain_tool_panic (m_libcassert.c:568)
==216962== by 0x58039828: vgMemCheck_eq_Error (mc_errors.c:1067)
==216962== by 0x5803E1B7: eq_Error (m_errormgr.c:307)
==216962== by 0x5803E1B7: vgPlain_maybe_record_error (m_errormgr.c:765)
==216962== by 0x580390A4: vgMemCheck_record_realloc_size_zero
(mc_errors.c:896)
==216962== by 0x5800599A: vgMemCheck_realloc (mc_malloc_wrappers.c:583)
==216962== by 0x580A029E: do_client_request (scheduler.c:1987)
==216962== by 0x580A029E: vgPlain_scheduler (scheduler.c:1542)
==216962== by 0x580E58BD: thread_wrapper (syswrap-linux.c:102)
==216962== by 0x580E58BD: run_a_thread_NORETURN (syswrap-linux.c:155)
sched status:
running_tid=1
Thread 1: status = VgTs_Runnable (lwpid 216962)
==216962== at 0x4846BE0: realloc (vg_replace_malloc.c:1649)
==216962== by 0x10960F: MAIN__ (example.f90:4)
==216962== by 0x10976F: main (example.f90:3)
client stack range: [0x1FFEFFE000 0x1FFF000FFF] client SP: 0x1FFF000130
valgrind stack range: [0x1002BAA000 0x1002CA9FFF] top usage: 10000 of 1048576
Note: see also the FAQ in the source distribution.
It contains workarounds to several common problems.
In particular, if Valgrind aborted or crashed after
identifying problems in your program, there's a good chance
that fixing those problems will prevent Valgrind aborting or
crashing, especially if it happened in m_mallocfree.c.
If that doesn't help, please report this bug to: www.valgrind.org
In the bug report, send all the above text, the valgrind
version, and what OS and version you are using. Thanks.
