MangoHud not loading with MANGOHUD=1 environment variable

[rafalb8]

Describe the bug

Starting programs with MANGOHUD=1 env variable doesn't load Mangohud.

Steps To Reproduce

Run this command:

MANGOHUD=1 vkgears

Expected behavior

MangoHud loaded and displayed on screen.

Additional context

Can be fixed temporarily by using LD_PRELOAD env variable.

LD_PRELOAD="/nix/store/gxcgm91cipxp5a3sxn0inqq3ylfb0dsc-mangohud-0.7.2/lib/mangohud/libMangoHud.so" MANGOHUD=1 vkgears

Metadata

 - system: `"x86_64-linux"`
 - host os: `Linux 6.12.8, NixOS, 24.11 (Vicuna), 24.11.20250106.3f0a8ac`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.24.11`
 - channels(root): `""`
 - nixpkgs: `/nix/store/fz4h8yz3qr83p6cfhisgj02knjqg6nxs-source`

Notify maintainers

@kira-bruneau @zeratax

---

Note for maintainers: Please tag this issue in your PR.

---

Add a 👍 reaction to issues you find important.

[kira-bruneau]

Thanks for the report @rafalb8! I tried on my system and it looks like there's a libc++ ABI conflict with spdlog.

I'm running the stable version of NixOS 24.11 and it's not uncommon to run into incompatibilities mixing graphical packages from different nixpkgs versions (See #95808). Based on the metadata you posted, it seems like you are too?

If you try this, do you get a similar output?

> LD_DEBUG=libs MANGOHUD=1 vkgears 2>&1 | grep error
    937673:	/nix/store/jzgr19jv2rvsl18269xqixchhh9fp04s-libdecor-0.2.2/lib/libdecor-0.so.0: error: symbol lookup error: undefined symbol: png_free (fatal)
    937673:	vkgears: error: symbol lookup error: undefined symbol: gtk_progress_get_type (fatal)
    937673:	/nix/store/4gk773fqcsv4fh2rfkhs9bgfih86fdq8-gcc-13.3.0-lib/lib/libstdc++.so.6: error: version lookup error: version `CXXABI_1.3.15' not found (required by /nix/store/izliy5ycacnyh940mvsjd48m448wp6cb-spdlog-1.14.1/lib/libspdlog.so.1.14) (fatal)
    937673:	/nix/store/j5y84h45sgs8ri200agp2ffxnkydha9w-mesa-24.2.8-drivers/lib/libVkLayer_MESA_device_select.so: error: symbol lookup error: undefined symbol: vkGetDeviceProcAddr (fatal)

I don't run into this problem if I use mangohud from the stable channel.

[rafalb8]

@kira-bruneau Yes, I'm using mangohud from unstable channel and rest of the system is on stable.

LD_DEBUG=libs MANGOHUD=1 vkgears 2>&1 | grep error
      7231:	/nix/store/crg433v9r6cb68a9d08i7whm3hh3vf62-nvidia-x11-565.77-6.12.8/lib/libnvidia-glcore.so.565.77: error: symbol lookup error: undefined symbol: __malloc_hook (fatal)
      7231:	/nix/store/crg433v9r6cb68a9d08i7whm3hh3vf62-nvidia-x11-565.77-6.12.8/lib/libnvidia-glcore.so.565.77: error: symbol lookup error: undefined symbol: __realloc_hook (fatal)
      7231:	/nix/store/crg433v9r6cb68a9d08i7whm3hh3vf62-nvidia-x11-565.77-6.12.8/lib/libnvidia-glcore.so.565.77: error: symbol lookup error: undefined symbol: __free_hook (fatal)
      7231:	/nix/store/crg433v9r6cb68a9d08i7whm3hh3vf62-nvidia-x11-565.77-6.12.8/lib/libnvidia-glcore.so.565.77: error: symbol lookup error: undefined symbol: __memalign_hook (fatal)
      7231:	/nix/store/crg433v9r6cb68a9d08i7whm3hh3vf62-nvidia-x11-565.77-6.12.8/lib/libnvidia-glcore.so.565.77: error: symbol lookup error: undefined symbol: ErrorF (fatal)
      7231:	/nix/store/ybjcla5bhj8g1y84998pn4a2drfxybkv-gcc-13.3.0-lib/lib/libstdc++.so.6: error: version lookup error: version `CXXABI_1.3.15' not found (required by /nix/store/izliy5ycacnyh940mvsjd48m448wp6cb-spdlog-1.14.1/lib/libspdlog.so.1.14) (fatal)
      7231:	/nix/store/crg433v9r6cb68a9d08i7whm3hh3vf62-nvidia-x11-565.77-6.12.8/lib/libnvidia-glcore.so.565.77: error: symbol lookup error: undefined symbol: dbus_get (fatal)
      7231:	/nix/store/141m63y55hh07jcry2lk5w2x5x5bg0b0-mesa-24.2.6-drivers/lib/libVkLayer_MESA_device_select.so: error: symbol lookup error: undefined symbol: vkGetDeviceProcAddr (fatal)

I also tried it on stable and it works properly.
Thanks.

[kira-bruneau]

I have a workaround for this included in #381317!

[kira-bruneau]

Never mind - during code review, we decided that it wouldn't be worth it to keep the workaround: #381317 (comment).