Perl using Wx yields core dump in debug mode (option -d)

Question

I have the following 3 line example to show the error:

use strict;
use warnings;
use Wx;

It works fine when I run it with perl -w hue5.pl . However, when I add the debugging option and start if with perl -w -d hue5.pl , a problem emerges and perl runtime crashes saying:

Loading DB routines from perl5db.pl version 1.55 Editor support available.

Enter h or 'hh' for help, or 'man perldebug' for more help.

Wx::CODE(0x5604c197ca80)(/usr/lib64/perl5/vendor_perl/Wx.pm:154): 154: UnsetConstants() if defined &UnsetConstants; double free or corruption (!prev) Aborted (core dumped)

I use perl v5.30.3 on 64 bit Linux (up-to-date Fedora release 31) and Wx installed from the binary package perl-Wx-0.9932-15.fc31.x86_64.rpm.

Is anybody else having this issue?

Answer 1

Short version: Uninstalling the package perl-Term-ReadLine-Gnu solved the issue.

Longer version: I saw that the issue does not always happen. In fact, it seems to depend on the size of the process environment. At one point of debugging I could make the crash appear by declaring in the bash (note: without export the issue does not show)

export SOMEVAR=xyz

and disappear by

unset SOMEVAR

Finally, during further experimentation, I once got a more elaborate failure message pointing right to Readline/Gnu:

Signal SEGV at /usr/lib64/perl5/vendor_perl/Term/ReadLine/Gnu.pm line 504. Term::ReadLine::Gnu::ornaments(Term::ReadLine=HASH(0x5593c12e5190), 1) > called at /usr/lib64/perl5/vendor_perl/Term/ReadLine/Gnu.pm line 301 Term::ReadLine::Gnu::new("Term::ReadLine", "perldb", GLOB(0x5593c062df58), GLOB(0x5593c05c6ea8)) called at /usr/share/perl5/perl5db.pl line 6865 DB::setterm() called at /usr/share/perl5/perl5db.pl line 1849 DB::_DB__read_next_cmd(undef) called at /usr/share/perl5/perl5db.pl line 2789 DB::DB called at f.pl line 5

For the curious , I note that line 504 in /usr/lib64/perl5/vendor_perl/Term/ReadLine/Gnu.pm was:

return Term::ReadLine::Gnu::XS::ornaments(@_);

For the even more curious I add strace dumps generated by runs which differ only with regard to the absence/presence of SOMEVAR in the environment (note that the name does not seem to have importance, I first got into the direction of environment differences by observing different behaviour depending on OLDPWD ).

First without the issue (ie without variable SOMEVAR ), quoting the lines as of loading Readline/Gnu library:

stat("/usr/lib65/perl5/vendor_perl/auto/Term/ReadLine/Gnu/XS/autosplit.ix", {st_mode=S_IFREG|0644, st_size=1137, ...}) = 0
openat(AT_FDCWD, "/usr/lib64/perl5/vendor_perl/auto/Term/ReadLine/Gnu/XS/autosplit.ix", O_RDONLY|O_CLOEXEC) = 13
ioctl(13, TCGETS, 0x7fff0a1cac70)       = -1 ENOTTY (Inappropriate ioctl for device)
lseek(13, 0, SEEK_CUR)                  = 0
read(13, "# Index created by AutoSplit for"..., 8192) = 1137
read(13, "", 8192)                      = 0
close(13)                               = 0
lseek(3, 2189, SEEK_SET)                = 2189
lseek(3, 0, SEEK_CUR)                   = 2189
close(3)                                = 0
getuid()                                = 1000
geteuid()                               = 1000
getgid()                                = 1000
getegid()                               = 1000
fcntl(4, F_GETFL)                       = 0x8002 (flags O_RDWR|O_LARGEFILE)
fcntl(5, F_GETFL)                       = 0x8002 (flags O_RDWR|O_LARGEFILE)
ioctl(1, TCGETS, {B38400 opost isig icanon echo ...}) = 0
stat("/home/bernhard/.terminfo", 0x55ec16193000) = -1 ENOENT (No such file or directory)
stat("/etc/terminfo", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
stat("/usr/share/terminfo", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
access("/etc/terminfo/x/xterm-256color", R_OK) = -1 ENOENT (No such file or directory)
access("/usr/share/terminfo/x/xterm-256color", R_OK) = 0
openat(AT_FDCWD, "/usr/share/terminfo/x/xterm-256color", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=3808, ...}) = 0
read(3, "\36\2%\0&\0\17\0\235\0010\6xterm-256color|xterm"..., 32768) = 3808
read(3, "", 28672)                      = 0
close(3)                                = 0
ioctl(1, TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(1, TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(1, TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(1, TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(1, TIOCGWINSZ, {ws_row=43, ws_col=173, ws_xpixel=0, ws_ypixel=0}) = 0
ioctl(4, TIOCGWINSZ, {ws_row=43, ws_col=173, ws_xpixel=0, ws_ypixel=0}) = 0
ioctl(4, TIOCGWINSZ, {ws_row=43, ws_col=173, ws_xpixel=0, ws_ypixel=0}) = 0
ioctl(4, TIOCSWINSZ, {ws_row=43, ws_col=173, ws_xpixel=0, ws_ypixel=0}) = 0
ioctl(4, TCGETS, {B38400 opost isig icanon echo ...}) = 0
openat(AT_FDCWD, "/home/bernhard/.inputrc", O_RDONLY) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/inputrc", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=943, ...}) = 0
read(3, "# do not bell on tab-completion\n"..., 943) = 943
close(3)                                = 0
brk(NULL)                               = 0x55ec1640f000
brk(0x55ec16430000)                     = 0x55ec16430000
stat("/usr/lib64/perl5/vendor_perl/auto/Term/ReadLine/Gnu/XS/ornaments.al", {st_mode=S_IFREG|0644, st_size=1351, ...}) = 0
geteuid()                               = 1000
geteuid()                               = 1000
getegid()                               = 1000
getgroups(0, NULL)                      = 2
getgroups(2, [18, 1000])                = 2
stat("/usr/lib64/perl5/vendor_perl/auto/Term/ReadLine/Gnu/XS/ornaments.al", {st_mode=S_IFREG|0644, st_size=1351, ...}) = 0
openat(AT_FDCWD, "/usr/lib64/perl5/vendor_perl/auto/Term/ReadLine/Gnu/XS/ornaments.al", O_RDONLY|O_CLOEXEC) = 3
ioctl(3, TCGETS, 0x7fff0a1cb9d0)        = -1 ENOTTY (Inappropriate ioctl for device)
lseek(3, 0, SEEK_CUR)                   = 0
read(3, "# NOTE: Derived from blib/lib/Te"..., 8192) = 1351
read(3, "", 8192)                       = 0
close(3)                                = 0
getpid()                                = 4060
getpid()                                = 4060
ioctl(4, TIOCGWINSZ, {ws_row=43, ws_col=173, ws_xpixel=0, ws_ypixel=0}) = 0
ioctl(4, TIOCSWINSZ, {ws_row=43, ws_col=173, ws_xpixel=0, ws_ypixel=0}) = 0
ioctl(4, TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(4, SNDCTL_TMR_STOP or TCSETSW, {B38400 opost isig -icanon -echo ...}) = 0
rt_sigprocmask(SIG_BLOCK, [HUP INT QUIT ALRM TERM TSTP TTIN TTOU], [], 8) = 0
rt_sigaction(SIGINT, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, 8) = 0
rt_sigaction(SIGTERM, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigaction(SIGHUP, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigaction(SIGQUIT, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigaction(SIGALRM, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigaction(SIGTSTP, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigaction(SIGTTOU, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigaction(SIGTTIN, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigaction(SIGWINCH, {sa_handler=0x7f4433da22f0, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART, sa_restorer=0x7f44490e46b0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
fstat(5, {st_mode=S_IFCHR|0666, st_rdev=makedev(0x5, 0), ...}) = 0
ioctl(5, TCGETS, {B38400 opost isig -icanon -echo ...}) = 0
write(5, "\33[4m  DB<1> \33[24m", 17)   = 17
pselect6(5, [4], NULL, NULL, NULL, {[], 8}) = 1 (in [4])
read(4, "q", 1)                         = 1
select(5, [4], NULL, [4], {tv_sec=0, tv_usec=0}) = 0 (Timeout)
write(5, "q", 1)                        = 1
pselect6(5, [4], NULL, NULL, NULL, {[], 8}) = 1 (in [4])
read(4, "\r", 1)                        = 1
write(5, "\n", 1)                       = 1
ioctl(4, SNDCTL_TMR_STOP or TCSETSW, {B38400 opost isig icanon echo ...}) = 0
rt_sigaction(SIGINT, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, 8) = 0
rt_sigaction(SIGTERM, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, 8) = 0
rt_sigaction(SIGHUP, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, 8) = 0
rt_sigaction(SIGQUIT, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, 8) = 0
rt_sigaction(SIGALRM, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, 8) = 0
rt_sigaction(SIGTSTP, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, 8) = 0
rt_sigaction(SIGTTOU, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, 8) = 0
rt_sigaction(SIGTTIN, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=0x7f4433da2e70, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, 8) = 0
rt_sigaction(SIGWINCH, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x7f44490e46b0}, {sa_handler=0x7f4433da22f0, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART, sa_restorer=0x7f44490e46b0}, 8) = 0
close(4)                                = 0
close(5)                                = 0
exit_group(0)                           = ?
+++ exited with 0 +++

Second with the issue (ie wit exported variable SOMEVAR ), again quoting only the lines as of loading Readline/Gnu library:

stat("/usr/lib64/perl5/vendor_perl/auto/Term/ReadLine/Gnu/XS/autosplit.ix", {st_mode=S_IFREG|0644, st_size=1137, ...}) = 0
openat(AT_FDCWD, "/usr/lib64/perl5/vendor_perl/auto/Term/ReadLine/Gnu/XS/autosplit.ix", O_RDONLY|O_CLOEXEC) = 13
ioctl(13, TCGETS, 0x7ffe8bf62e00)       = -1 ENOTTY (Inappropriate ioctl for device)
lseek(13, 0, SEEK_CUR)                  = 0
read(13, "# Index created by AutoSplit for"..., 8192) = 1137
read(13, "", 8192)                      = 0
close(13)                               = 0
lseek(3, 2189, SEEK_SET)                = 2189
lseek(3, 0, SEEK_CUR)                   = 2189
close(3)                                = 0
getuid()                                = 1000
geteuid()                               = 1000
getgid()                                = 1000
getegid()                               = 1000
fcntl(4, F_GETFL)                       = 0x8002 (flags O_RDWR|O_LARGEFILE)
fcntl(5, F_GETFL)                       = 0x8002 (flags O_RDWR|O_LARGEFILE)
ioctl(1, TCGETS, {B38400 opost isig icanon echo ...}) = 0
stat("/home/bernhard/.terminfo", 0x55b600a2b5a0) = -1 ENOENT (No such file or directory)
stat("/etc/terminfo", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
stat("/usr/share/terminfo", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
access("/etc/terminfo/x/xterm-256color", R_OK) = -1 ENOENT (No such file or directory)
access("/usr/share/terminfo/x/xterm-256color", R_OK) = 0
openat(AT_FDCWD, "/usr/share/terminfo/x/xterm-256color", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=3808, ...}) = 0
read(3, "\36\2%\0&\0\17\0\235\0010\6xterm-256color|xterm"..., 32768) = 3808
read(3, "", 28672)                      = 0
close(3)                                = 0
ioctl(1, TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(1, TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(1, TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(1, TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(1, TIOCGWINSZ, {ws_row=43, ws_col=173, ws_xpixel=0, ws_ypixel=0}) = 0
ioctl(4, TIOCGWINSZ, {ws_row=43, ws_col=173, ws_xpixel=0, ws_ypixel=0}) = 0
writev(2, [{iov_base="double free or corruption (!prev"..., iov_len=33}, {iov_base="\n", iov_len=1}], 2) = 34
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f376a2e3000
rt_sigprocmask(SIG_UNBLOCK, [ABRT], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, ~[RTMIN RT_1], [], 8) = 0
getpid()                                = 4029
gettid()                                = 4029
tgkill(4029, 4029, SIGABRT)             = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
--- SIGABRT {si_signo=SIGABRT, si_code=SI_TKILL, si_pid=4029, si_uid=1000} ---
+++ killed by SIGABRT (core dumped) +++