ponyc: pony-lsp crashes with SIGILL

Nixpkgs version

• Unstable (26.11)

Describe the bug

When trying to use pony-lsp in a code editor it crashes with illegal instruction (core dumped). This seems to only affect pony-lsp but not ponyc

Steps to reproduce

1. Not have AVX512 support.
2. Setup pony-lsp in your code editor
3. Observe the crash

Expected behaviour

pony-lsp isn't supposed to crash with illegal instruction.

Screenshots

No response

Relevant log output

[jsonrpc] D[16:29:01.512] Running language server: pony-lsp
[jsonrpc] e[16:29:01.517] --> initialize[1] {"jsonrpc":"2.0","id":1,"method":"initialize","params":{"processId":545889,"clientInfo":{"name":"Eglot","version":"1.17.30"},"rootPath":"/home/vavakado/Development/projects/personal/pony/tryout/","rootUri":"file:///home/vavakado/Development/projects/personal/pony/tryout","initializationOptions":{},"capabilities":{"workspace":{"applyEdit":true,"executeCommand":{"dynamicRegistration":false},"workspaceEdit":{"documentChanges":true},"didChangeWatchedFiles":{"dynamicRegistration":true},"symbol":{"dynamicRegistration":false},"configuration":true,"workspaceFolders":true},"textDocument":{"synchronization":{"dynamicRegistration":false,"willSave":true,"willSaveWaitUntil":true,"didSave":true},"completion":{"dynamicRegistration":false,"completionItem":{"snippetSupport":true,"deprecatedSupport":true,"resolveSupport":{"properties":["documentation","details","additionalTextEdits"]},"tagSupport":{"valueSet":[1]}},"contextSupport":true},"hover":{"dynamicRegistration":false,"contentFormat":["markdown","plaintext"]},"signatureHelp":{"dynamicRegistration":false,"signatureInformation":{"parameterInformation":{"labelOffsetSupport":true},"documentationFormat":["markdown","plaintext"],"activeParameterSupport":true}},"references":{"dynamicRegistration":false},"definition":{"dynamicRegistration":false,"linkSupport":true},"declaration":{"dynamicRegistration":false,"linkSupport":true},"implementation":{"dynamicRegistration":false,"linkSupport":true},"typeDefinition":{"dynamicRegistration":false,"linkSupport":true},"documentSymbol":{"dynamicRegistration":false,"hierarchicalDocumentSymbolSupport":true,"symbolKind":{"valueSet":[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26]}},"documentHighlight":{"dynamicRegistration":false},"codeAction":{"dynamicRegistration":false,"resolveSupport":{"properties":["edit","command"]},"dataSupport":true,"codeActionLiteralSupport":{"codeActionKind":{"valueSet":["quickfix","refactor","refactor.extract","refactor.inline","refactor.rewrite","source","source.organizeImports"]}},"isPreferredSupport":true},"formatting":{"dynamicRegistration":false},"rangeFormatting":{"dynamicRegistration":false},"rename":{"dynamicRegistration":false},"inlayHint":{"dynamicRegistration":false},"publishDiagnostics":{"relatedInformation":false,"codeDescriptionSupport":false,"tagSupport":{"valueSet":[1,2]}}},"window":{"showDocument":{"support":true},"workDoneProgress":true},"general":{"positionEncodings":["utf-32","utf-8","utf-16"]},"experimental":{}},"workspaceFolders":[{"uri":"file:///home/vavakado/Development/projects/personal/pony/tryout","name":"~/Development/projects/personal/pony/tryout/"}]}}
[jsonrpc] e[16:29:01.626] <-- window/logMessage {"method":"window/logMessage","jsonrpc":"2.0","params":{"type":5,"message":"Connected to client: Eglot-1.17.30 (545889)\r\nsupports:\r\n\tconfiguration\r\n\tpublish diagnostics\r\n\tserver-initiated workDoneProgress\r\n"}}
[jsonrpc] e[16:29:01.626] <-- window/logMessage {"method":"window/logMessage","jsonrpc":"2.0","params":{"type":5,"message":"Scanning workspace file:///home/vavakado/Development/projects/personal/pony/tryout"}}
[jsonrpc] D[16:29:03.507] Connection state change: `illegal instruction (core dumped)

Additional context

I tried this in neovim, helix and emacs, and the issue isn't editor-dependent. It seems to be related to #491562.

System metadata

• system: "x86_64-linux"
• host os: Linux 7.0.12-cachyos-lto, NixOS, 26.11 (Zokor), 26.11.20260610.9ae611a
• multi-user?: yes
• sandbox: yes
• version: nix-env (Lix, like Nix) 2.94.2 System type: x86_64-linux Additional system types: i686-linux, x86_64-v1-linux, x86_64-v2-linux, x86_64-v3-linux Features: gc, signed-caches System configuration file: /etc/nix/nix.conf User configuration files: /home/vavakado/.config/nix/nix.conf:/etc/xdg/nix/nix.conf:/home/vavakado/.local/share/flatpak/exports/etc/xdg/nix/nix.conf:/var/lib/flatpak/exports/etc/xdg/nix/nix.conf:/home/vavakado/.nix-profile/etc/xdg/nix/nix.conf:/nix/profile/etc/xdg/nix/nix.conf:/home/vavakado/.local/state/nix/profile/etc/xdg/nix/nix.conf:/etc/profiles/per-user/vavakado/etc/xdg/nix/nix.conf:/nix/var/nix/profiles/default/etc/xdg/nix/nix.conf:/run/current-system/sw/etc/xdg/nix/nix.conf Store directory: /nix/store State directory: /nix/var/nix Data directory: /nix/store/1d0v39m4796y20lgc8xmcc240fj522v8-lix-2.94.2/share
• nixpkgs: /nix/store/gw7fxaw8z5szcqlzyzcnrshzi60zj664-source

Notify maintainers

@kamilchm @redvers @numinit

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Start by reproducing pony-lsp on x86_64-linux without AVX512 support and compare its behavior with ponyc. Review the package and build context alongside related issue #491562; done means pony-lsp initializes and scans a workspace without an illegal-instruction crash.