[ARM64] zend_mm_heap corrupted with ZTS builds (Static PHP 8.5.2)

[maks-oleksyuk]

Description

On ARM64 (aarch64) architecture, ZTS builds of PHP 8.5.2 cause zend_mm_heap corrupted errors when running Laravel Pint. The same code works fine on x86_64.

Cross-platform comparison:

Architecture	Build	Result
x86_64	Static PHP 8.5.2 ZTS	✅ Works
aarch64	Static PHP 8.5.2 ZTS	❌ Crashes with zend_mm_heap corrupted

Key details:

• Built with: zig 0.15.2
• ZTS (Zend Thread Safety): enabled
• Architecture: aarch64 (ARM64 - Apple Silicon M4)

Minimal Reproduction Case

Laravel Pint can be used as a reliable reproduction case:

# Install Pint
composer require laravel/pint

# Run version command - this crashes on ARM64 ZTS
php vendor/bin/pint --version

Expected output:

Pint 1.27.0

Actual output on ARM64 ZTS:

zend_mm_heap corrupted
bash: line 1:  2005 Aborted                 ( php vendor/bin/pint --version )
exit status 134

Workaround

Setting USE_ZEND_ALLOC=0 environment variable fixes the issue:

USE_ZEND_ALLOC=0 php vendor/bin/pint --version
# Output: Pint 1.27.0

This forces PHP to use system memory allocator (malloc) instead of Zend Memory Manager.

PHP Configuration

memory_limit => 1024M
Zend Memory Manager => enabled
ZTS => yes
JIT => Disabled

The same PHP version (8.5.2 ZTS) works fine on x86_64 but fails on aarch64

PHP Version

PHP 8.5.2 (cli) (built: Jan 16 2026 02:41:43) (ZTS zig 0.15.2 aarch64)
Copyright (c) The PHP Group
Built by Static PHP <https://static-php.dev> #StandWithUkraine
Zend Engine v4.5.2, Copyright (c) Zend Technologies
    with Zend OPcache v8.5.2, Copyright (c), by Zend Technologies

Operating System

MacOS Tahoe 26.2

[iluuu1994]

FWIU zig wraps clang. Do you get the same issue when building with clang directly?

[maks-oleksyuk]

@iluuu1994 I tried running it like this, and it works using this build.

PHP 8.5.2 (cli) (built: Jan 16 2026 23:18:27) (ZTS)
Copyright (c) The PHP Group
Built by https://github.com/docker-library/php
Zend Engine v4.5.2, Copyright (c) Zend Technologies
    with Zend OPcache v8.5.2, Copyright (c), by Zend Technologies

docker run --rm -v "$(pwd):/app" -w /app php:8.5-zts php /app/vendor/bin/pint --version 

If you need any other information, please provide more specific instructions on what I need to do or test. Thank you.

[iluuu1994]

Where did you obtain the Zig build? Or did you build it yourself?

[maks-oleksyuk]

I found an error when using ddev and their images.

[henderkes]

Where did you obtain the Zig build? Or did you build it yourself?

# try in a docker container
sudo curl https://pkg.henderkes.com/api/packages/85/debian/repository.key -o /etc/apt/keyrings/static-php85.asc
echo "deb [signed-by=/etc/apt/keyrings/static-php85.asc] https://pkg.henderkes.com/api/packages/85/debian php-zts main" | sudo tee /etc/apt/sources.list.d/static-php85.list
sudo apt update && sudo install -y php-zts

zig 15.x bundles LLVM/Clang 21. I don't have a build matrix using Clang directly, but I can build with it once if you want.

I can't reproduce the issue on any of the arm hardware I have and rent.

Edit: @maks-oleksyuk you should also link to the project you're running into the issue with so someone can possibly reproduce this. I forgot what project it was. Perhaps you can create a Docker image with the project code and php-zts installed that someone can simply run docker run maks/crashing-reproducer:latest php-zts /app/vendor/bin/pint ....

Edit2: debuginfo packages are available for php too. apt install -y php-zts-cli-debuginfo in the container.

[iluuu1994]

I found an error when using ddev and their images.

That's odd, I can't find a reference to Zig in their Docker files. I confirmed by running the default image, which doesn't seem to be built with Zig (or at least doesn't specify so). Can you clarify exactly which tag you're using? I.e. please provide full instructions on how to reproduce the issue.

@henderkes Just to clarify, did you build with Clang or Zig? My fear is just that something in Zig leads to a miscompilation. "zend_mm_heap corrupted" usually occurs when there's some memory corruption.

[stasadev]

That's odd, I can't find a reference to Zig in their Docker files. I confirmed by running the default image, which doesn't seem to be built with Zig (or at least doesn't specify so). Can you clarify exactly which tag you're using? I.e. please provide full instructions on how to reproduce the issue.

DDEV maintainer here, just to clarify a misunderstanding: we do not build PHP ZTS. We only install it in our images using packages provided by @henderkes. Everything happens in https://github.com/ddev/ddev-frankenphp.

That said, it does not really matter here:

mkdir test && cd test
composer create-project laravel/laravel .
docker run --rm -v "$(pwd):/app" ddev/ddev-webserver:v1.24.10 bash -c "sudo curl https://pkg.henderkes.com/api/packages/85/debian/repository.key -o /etc/apt/keyrings/static-php85.asc && echo 'deb [signed-by=/etc/apt/keyrings/static-php85.asc] https://pkg.henderkes.com/api/packages/85/debian php-zts main' | sudo tee /etc/apt/sources.list.d/static-php85.list && sudo apt-get update && sudo apt-get install -y php-zts && sudo cp /etc/php/8.5/fpm/php.ini /etc/php-zts/php.ini && php-zts /app/vendor/bin/pint --version"

[rfay]

I can reproduce using that repro one-liner on an arm64 machine:

The following NEW packages will be installed:
  php-zts-cli
0 upgraded, 1 newly installed, 0 to remove and 163 not upgraded.
Need to get 9736 kB of archives.
After this operation, 43.1 MB of additional disk space will be used.
Get:1 https://pkg.henderkes.com/api/packages/85/debian php-zts/main arm64 php-zts-cli arm64 8.5.2-1 [9736 kB]
debconf: delaying package configuration, since apt-utils is not installed
Fetched 9736 kB in 2s (6373 kB/s)
Selecting previously unselected package php-zts-cli.
(Reading database ... 22035 files and directories currently installed.)
Preparing to unpack .../php-zts-cli_8.5.2-1_arm64.deb ...
Unpacking php-zts-cli (8.5.2-1) ...
Setting up php-zts-cli (8.5.2-1) ...
zend_mm_heap corrupted

[henderkes]

Yep I'm getting it too now.

(gdb) run

Starting program: /usr/bin/php-zts /app/vendor/bin/pint --version

warning: Error disabling address space randomization: Operation not permitted

[Thread debugging using libthread_db enabled]

Using host libthread_db library "/lib/aarch64-linux-gnu/libthread_db.so.1".

zend_mm_heap corrupted



Program received signal SIGABRT, Aborted.

__pthread_kill_implementation (threadid=281473649352736, signo=signo@entry=6, no_tid=no_tid@entry=0)

    at ./nptl/pthread_kill.c:44

44      ./nptl/pthread_kill.c: No such file or directory.

(gdb) bt full

#0  __pthread_kill_implementation (threadid=281473649352736, signo=signo@entry=6, no_tid=no_tid@entry=0)

    at ./nptl/pthread_kill.c:44

        tid = 951

        ret = 0

        pd = 0xffffb0e22020

        old_mask = {__val = {281473643646976}}

        ret = <optimized out>

#1  0x0000ffffb0bf3c64 in __pthread_kill_internal (signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:78

No locals.

#2  0x0000ffffb0baa8ac in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26

        ret = <optimized out>

#3  0x0000ffffb0b97480 in __GI_abort () at ./stdlib/abort.c:79

        save_stage = 1

        act = {__sigaction_handler = {sa_handler = 0x20, sa_sigaction = 0x20}, sa_mask = {__val = {

              11449998757343416576, 281474496496560, 187650418873112, 7599935559840047114, 755771561678547060, 0, 0,

              0, 281474496488328, 0, 0, 3689348814741910323, 3689348814741910323, 3377699922640896, 0, 0}},

          sa_flags = 0, sa_restorer = 0x0}

#4  0x0000aaaac48f1324 in zend_mm_panic (message=<optimized out>)

    at /__w/packages/packages/source/php-src/Zend/zend_alloc.c:392

No locals.

#5  0x0000aaaac48f6ac0 in zend_mm_free_heap (heap=0x83, ptr=<optimized out>)

    at /__w/packages/packages/source/php-src/Zend/zend_alloc.c:1203

        chunk = 0x3b7

        page_num = <optimized out>

        page_offset = <optimized out>

#6  _efree (ptr=<optimized out>) at /__w/packages/packages/source/php-src/Zend/zend_alloc.c:2794

No locals.

#7  0x0000aaaac48968a8 in php_stream_filter_free (filter=0x0)

    at /__w/packages/packages/source/php-src/main/streams/filter.c:280

--Type <RET> for more, q to quit, c to continue without paging--

No locals.

#8  php_stream_filter_remove (filter=<optimized out>, call_dtor=<optimized out>)

    at /__w/packages/packages/source/php-src/main/streams/filter.c:505

No locals.

Backtrace stopped: previous frame identical to this frame (corrupt stack?)

@henderkes Just to clarify, did you build with Clang or Zig? My fear is just that something in Zig leads to a miscompilation. "zend_mm_heap corrupted" usually occurs when there's some memory corruption.

With zig 15.2, which is just a frontend for clang. I'm recompiling with clang 21 right now to see if that changes anything.

[henderkes]

https://files.henderkes.com/aarch64-linux/php-zts-cli_8.5.2-1_arm64.deb and https://files.henderkes.com/aarch64-linux/php-zts-cli-debuginfo_8.5.2-1_arm64.deb are ready for download.

However, as to kind of be expected, they emit the same behaviour:

docker run --rm -v "$(pwd):/app" ddev/ddev-webserver:v1.24.10 bash -c "
    curl -LO https://files.henderkes.com/aarch64-linux/php-zts-cli_8.5.2-1_arm64.deb && \
    curl -LO https://files.henderkes.com/aarch64-linux/php-zts-cli-debuginfo_8.5.2-1_arm64.deb && \
    sudo apt-get update && \
    sudo apt-get install -y ./php-zts-cli_8.5.2-1_arm64.deb ./php-zts-cli-debuginfo_8.5.2-1_arm64.deb && \
    sudo mkdir -p /etc/php-zts && \
    ([ -f /etc/php/8.5/fpm/php.ini ] && sudo cp /etc/php/8.5/fpm/php.ini /etc/php-zts/php.ini || echo 'no source ini found') && \
    php-zts /app/vendor/bin/pint --version
"
...
Get:1 /php-zts-cli_8.5.2-1_arm64.deb php-zts-cli arm64 8.5.2-1 [9763 kB]
Get:2 /php-zts-cli-debuginfo_8.5.2-1_arm64.deb php-zts-cli-debuginfo arm64 8.5.2-1 [10.1 MB]
debconf: delaying package configuration, since apt-utils is not installed
Selecting previously unselected package php-zts-cli.
(Reading database ... 22035 files and directories currently installed.)
Preparing to unpack /php-zts-cli_8.5.2-1_arm64.deb ...
Unpacking php-zts-cli (8.5.2-1) ...
Selecting previously unselected package php-zts-cli-debuginfo.
Preparing to unpack .../php-zts-cli-debuginfo_8.5.2-1_arm64.deb ...
Unpacking php-zts-cli-debuginfo (8.5.2-1) ...
Setting up php-zts-cli (8.5.2-1) ...
Setting up php-zts-cli-debuginfo (8.5.2-1) ...
zend_mm_heap corrupted

[henderkes]

Added gcc compiled packages:

docker run --rm -v "$(pwd):/app" ddev/ddev-webserver:v1.24.10 bash -c "
    curl -LO https://files.henderkes.com/aarch64-linux/php-zts-cli_8.5.2-2_arm64.deb && \
    curl -LO https://files.henderkes.com/aarch64-linux/php-zts-cli-debuginfo_8.5.2-2_arm64.deb && \
    sudo apt-get update && \
    sudo apt-get install -y ./php-zts-cli_8.5.2-2_arm64.deb ./php-zts-cli-debuginfo_8.5.2-2_arm64.deb && \
    sudo mkdir -p /etc/php-zts && \
    ([ -f /etc/php/8.5/fpm/php.ini ] && sudo cp /etc/php/8.5/fpm/php.ini /etc/php-zts/php.ini || echo 'no source ini found') && \
    php-zts /app/vendor/bin/pint --version
"
->
Preparing to unpack /php-zts-cli_8.5.2-2_arm64.deb ...
Unpacking php-zts-cli (8.5.2-2) ...
Selecting previously unselected package php-zts-cli-debuginfo.
Preparing to unpack .../php-zts-cli-debuginfo_8.5.2-2_arm64.deb ...
Unpacking php-zts-cli-debuginfo (8.5.2-2) ...
Setting up php-zts-cli (8.5.2-2) ...
Setting up php-zts-cli-debuginfo (8.5.2-2) ...
Pint 1.27.0

The error may be related to the tail call vm?