I put in the xdebug.ini from 2.9, here is my 3.0.1:

zend_extension=/usr/lib64/php7.4/lib/extensions/no-debug-zts-20190902/xdebug.so
;xdebug.cli_color = 0
;xdebug.client_discovery_header =
;xdebug.client_host = localhost
;xdebug.client_port = 9003
;xdebug.collect_params = 0
;xdebug.collect_return = 0
;xdebug.connect_timeout_ms = 200
;xdebug.discover_client_host = 0
;xdebug.dump. = Empty
;xdebug.dump_globals = 1
;xdebug.dump_once = 1
;xdebug.dump_undefined = 0
;xdebug.file_link_format =
;xdebug.filename_format = ...%s%n
;xdebug.force_display_errors = 0
;xdebug.force_error_reporting = 0
;xdebug.gc_stats_output_name = gcstats.%p
;xdebug.halt_level = 0
;xdebug.idekey = complex*
;xdebug.log =
;xdebug.log_level = 7
;xdebug.max_nesting_level = 256
;xdebug.max_stack_frames = -1
xdebug.mode=off
;xdebug.output_dir = /tmp
;xdebug.profiler_append = 0
;xdebug.profiler_output_name = cachegrind.out.%p
;xdebug.scream = 0
;xdebug.show_error_trace = 0
;xdebug.show_exception_trace = 0
;xdebug.show_local_vars = 0
;xdebug.start_upon_error = default
;xdebug.start_with_request = default
;xdebug.trace_format = 0
;xdebug.trace_options = 0
;xdebug.trace_output_dir = /tmp
;xdebug.trace_output_name = trace.%c
;xdebug.trigger_value = ""
;xdebug.var_display_max_children = 128
;xdebug.var_display_max_data = 512
;xdebug.var_display_max_depth = 3

Can you provide the exact steps (git clone, composer install, etc) for me to try to reproduce this problem?

Hi Derick,

Thanks for taking a look at this. I am using gentoo AMD Ryzen 7 3700X 8-Core Processor, cflags = "-march=native -mtune=native -O2 -ftree-vectorize -fomit-frame-pointer -ggdb -pipe". Composer version: 1.10.15

The following produces two segfaults. First segfault happens on composer install and the second on phpcs. Seems to happen every time for me.

git clone git@github.com:FaaPz/PDO.git
composer install
vendor/bin/phpcs -s --standard=phpcs.xml

Problem still persists with xdebug 3.0.2

I have tried reproducing this (with xdebug 3.0.3-dev), but I am not getting any segfault, or any other warnings when running with valgrind like this either:

<code>
USE_ZEND_ALLOC=0 valgrind php -f vendor/bin/phpcs -- -s --standard=phpcs.xml
</code>

Your original backtrace doesn't show that Xdebug is involved in the crash either... So unless you can come up with something that allows me to see the problem locally, I am not sure what I can do.

This bug is the same as https://bugs.xdebug.org/view.php?id=1934, my best guess is xdebug is getting unloaded twice but I'll see if I can get a better trace in the other bug.

I got a bunch of segfaults yesterday that started out as php errors, but were crashing fpm. I haven't investigated them but my best guess is Xdebug (call me grinch :D). Have you managed to reproduce it or should I try to rollback the code and see if I can generate a dump?

I can reproduce it every time I run php but my GDB skills are pretty poor. This segfault seems to be related to unloading the xdebug extension when ZTS is enabled. I suspect it is getting unloaded twice or this is some other type of race condition going on when PHP is cleaning itself up. If you have an idea about something I should try with GDB or anything else let me know. If I disable ZTS things do work normally.

My configuration:

./configure --prefix=/usr --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --mandir=/usr/share/man --infodir=/usr/share/info --datadir=/usr/share --sysconfdir=/etc --localstatedir=/var/lib --docdir=/usr/share/doc/php-7.4.14-r1 --htmldir=/usr/share/doc/php-7.4.14-r1/html --prefix=/usr/lib64/php7.4 --mandir=/usr/lib64/php7.4/man --infodir=/usr/lib64/php7.4/info --libdir=/usr/lib64/php7.4/lib --with-libdir=lib64 --localstatedir=/var --without-pear --enable-maintainer-zts --without-password-argon2 --enable-bcmath --with-bz2=/usr --disable-calendar --disable-gcov --enable-ctype --with-curl --enable-dom --without-enchant --disable-exif --without-ffi --enable-fileinfo --enable-filter --enable-ftp --with-gettext=/usr --without-gmp --without-mhash --with-iconv --disable-intl --disable-ipv6 --enable-json --without-kerberos --with-libxml --enable-mbstring --with-openssl --enable-pcntl --enable-phar --enable-pdo --enable-opcache --without-pgsql --enable-posix --with-pspell=/usr --enable-simplexml --disable-shmop --without-snmp --enable-soap --enable-sockets --without-sodium --with-sqlite3 --enable-sysvmsg --enable-sysvsem --enable-sysvshm --without-tidy --enable-tokenizer --enable-xml --disable-xmlreader --enable-xmlwriter --without-xmlrpc --without-xsl --with-zip --with-zlib=/usr --disable-debug --enable-dba --without-cdb --with-db4=/usr --enable-flatfile --with-gdbm=/usr --disable-inifile --without-qdbm --without-tcadb --without-lmdb --without-freetype --disable-gd-jis-conv --without-jpeg --without-xpm --without-webp --disable-gd --without-mysqli --with-mysql-sock=/var/run/mysqld/mysqld.sock --without-unixODBC --without-iodbc --without-pdo-odbc --without-oci8 --without-pdo-dblib --with-pdo-mysql=mysqlnd --without-pdo-pgsql --with-pdo-sqlite --without-pdo-firebird --without-pdo-oci --with-readline=/usr --without-libedit --without-mm --with-pic --with-external-pcre --without-pcre-jit --cache-file=/var/tmp/portage/dev-lang/php-7.4.14-r1/temp/config.cache --with-config-file-path=/etc/php/cli-php7.4 --with-config-file-scan-dir=/etc/php/cli-php7.4/ext-active --disable-embed --enable-cli --disable-cgi --disable-fpm --without-apxs2 --disable-phpdbg

Confirming this. Using the docker image 7.3-apache-stretch with "pecl install xdebug" and XDEBUG_MODE="develop,debug" XDEBUG_CONFIG="cli_color=1 client_host=192.168.64.1 client_port=9000 discover_client_host=0 start_with_request=1"
Seeing segmentation faults on random phpunit tests
Had to revert back to 2.9.8

I can reproduce this error in a docker container running php7.3 & xdebug 3.0.2. Random tests are failing, depending if i call phpunit with or without --testdox. It only happens with xdebug.mode=develop. every other mode is fine, and every combination without develop is fine.
I attached a gdb stacktrace.

Same issue on a private repository (can't provide source code to reproduce)
Random segfault when execute phpunit tests on our dev docker container (with xDebug)
Work fine with our production container (without xDebug)

PHP 8.0.0 (cli) (built: Dec 1 2020 03:33:03) ( NTS )
Copyright (c) The PHP Group
Zend Engine v4.0.0-dev, Copyright (c) Zend Technologies
with Zend OPcache v8.0.0, Copyright (c), by Zend Technologies
with Xdebug v3.0.3, Copyright (c) 2002-2021, by Derick Rethans

[Xdebug]
xdebug.max_nesting_level = 1000
xdebug.remote_enable=On
xdebug.remote_port=9500
xdebug.remote_connect_back=On
xdebug.idekey=PHPSTORM
xdebug.remote_host=localhost
xdebug.cli_color=1
xdebug.var_display_max_depth=10

Hi Derick,

I have tracked the issue to --disable-debug configuration. If it is disabled, it crashes for me every time with php -v and xdebug 3.0.x. I am not sure why this is the case as I can't really get a good stack trace without --enable -debug but hopefully this can help reproduce the issue.

Hi,

I've just tried reproducing this again, but it still does not produce any crashes, or valgrind errors with php 7.4.13 in non-debug mode, and Xdebug also not compiled in debug mode. Perhaps this is a compiler or libc inconsistency, but as long as I can't reproduce this... I'm going to be in the dark.

If somebody can manage to create a docker setup, where I can ssh-in and run a PHP CLI command, and where also gdb, valgrind, and strace are installed, I can give that a go.

cheers,
Derick

Unless I get the requested additional information, I will be closing this report in the next week or so.

Closing this, as I can't either reproduce this, or not enough information has been provided, even after soliciting feedback again.