Critical WeChat Mini Program Crash on ARM (Box64) — Affects SW64 and Raspberry Pi 5

[luoqiaoling]

Hi ptitSeb,

First of all, thank you for your incredible work on Box64 — it’s truly a game-changer for running x86 Linux applications on ARM devices like the Raspberry Pi 5. Your contributions have opened up countless possibilities for ARM-based platforms, and we deeply appreciate it.

We’re currently porting Box64 to SW64, a custom ARM-compatible platform. During testing, we encountered a critical issue with WeChat that also appears on mainstream devices such as the Raspberry Pi 5 running vanilla Box64 — indicating a potential issue in Box64’s translation layer itself.

🐛 Issue Summary
App: WeChat (ARM version) running x86 components via Box64

Problem: Launching a Mini Program causes a crash

Error: free(): invalid pointer — appears related to mmap’d memory not being freed correctly

Affected platforms:

✅ SW64 (Box64 ported)

✅ Raspberry Pi 5 (Box64 upstream)

❌ Not platform-specific — appears Box64-related

We’ve already tried using BOX64_MALLOC_HACK=2, but the crash still occurs.

🚨 Why This Matters
Mini Programs are core to the WeChat experience (used daily by over 1.3 billion users)

On SW64, native ARM WeChat alone isn’t enough — x86 compatibility is essential for broader Linux app support

This issue affects adoption and usability of Box64 in real-world, user-critical scenarios

🙏 Request
Would you be able to investigate this edge case?

Fixing this would make Box64 even more transformative — not just technically, but in enabling ARM platforms like SW64 to meet real-world user expectations at scale.

WeChatLinux_x86_64.deb can be donwloaded on https://linux.weixin.qq.com/

Thanks again for everything you’ve done — we’re excited to see where Box64 goes next!

[ptitSeb]

Not sure I fully understand the ticket:

1. WeChat on ARM exist, but the "Mini Programs" functionnality doesn't work on ARM?
2. WeChat on x86_64 works with box64, but not the "Mini Programs" functionnality that fails with a "free - invalid pointer" error, even when BOX64_MALLOC_HACK=2 is used.

Do you know what "Mini Programs" actually are? libraries? binaries executable? custom stuffs loaded into memory and run?
Also, pretty sure I need a WeChat account to be able to debug that one right?

(side note: are you using AI to format the ticket? if yes, please stop, it's way too verbose)

(side side note, why is this a discution and not an issue?)