ZLS completely breaks in various ways when reading std.os.linux source.

[The-Briel-Deal]

Zig Version

0.15.0-dev.1145+3ae0ba096

ZLS Version

0.15.0-dev.293+45b855f7

Client / Code Editor / Extensions

nvim with lspconfig, also occurs with vscode zig extension

Steps to Reproduce and Observed Behavior

1. Clone Zig compiler source code (latest master).
2. Browse to https://github.com/ziglang/zig/blob/master/lib/std/os/linux.zig in your editor.

When I open this file in nvim, the inline hints are completely wrong, syntax highlighting is all over the place, hover doesn't work, it almost looks like zls is returning uninitialized memory to my editor.

When I open this file in vscode (or code-oss, which is a fork), I get a message saying that zls crashed 5 times within 3 minutes so it is giving up on restarting.

Expected Behavior

I would expect normal zls behavior in this file since it is valid and compilable zig code.

Relevant log output

2025-07-19 13:03:21.187 [info] Starting ZLS      0.15.0-dev.293+45b855f7 @ '/home/gabe/.config/Code - OSS/User/globalStorage/ziglang.vscode-zig/zls/x86_64-linux-0.15.0-dev.293+45b855f7/zls'
2025-07-19 13:03:21.187 [info] Log File:         /home/gabe/.cache/zls/zls.log (info)
2025-07-19 13:03:21.187 [info] Client Info:      Code - OSS (1.101.1)
2025-07-19 13:03:21.187 [info] Autofix Mode:     'source.fixall'
2025-07-19 13:03:21.187 [info] added Workspace Folder: file:///home/gabe/Code/zig
2025-07-19 13:03:21.196 [info] Set config option 'builtin_path' to "/home/gabe/.cache/zls/builtin.zig"
2025-07-19 13:03:21.196 [info] Set config option 'zig_lib_path' to "/home/gabe/.zvm/master/lib"
2025-07-19 13:03:21.197 [info] Set config option 'zig_exe_path' to "/home/gabe/.zvm/bin/zig"
2025-07-19 13:03:21.197 [info] Set config option 'build_runner_path' to "/home/gabe/.cache/zls/build_runner/1d53bc737952080cbb4ceac8f3674c20/build_runner.zig"
2025-07-19 13:03:21.197 [info] Set config option 'global_cache_path' to "/home/gabe/.cache/zls"
2025-07-19 13:03:21.211 [info] Loaded build file 'file:///home/gabe/Code/zig/build.zig'
2025-07-19 13:03:21.809 [error] error (default): ParseError
2025-07-19 13:03:21.809 [error] Server process exited with code 1.
2025-07-19 13:03:21.810 [info] Connection to server got closed. Server will restart.
2025-07-19 13:03:21.816 [info] Starting ZLS      0.15.0-dev.293+45b855f7 @ '/home/gabe/.config/Code - OSS/User/globalStorage/ziglang.vscode-zig/zls/x86_64-linux-0.15.0-dev.293+45b855f7/zls'
2025-07-19 13:03:21.816 [info] Log File:         /home/gabe/.cache/zls/zls.log (info)
2025-07-19 13:03:21.816 [info] Client Info:      Code - OSS (1.101.1)
2025-07-19 13:03:21.816 [info] Autofix Mode:     'source.fixall'
2025-07-19 13:03:21.816 [info] added Workspace Folder: file:///home/gabe/Code/zig
2025-07-19 13:03:21.822 [info] Set config option 'builtin_path' to "/home/gabe/.cache/zls/builtin.zig"
2025-07-19 13:03:21.822 [info] Set config option 'zig_lib_path' to "/home/gabe/.zvm/master/lib"
2025-07-19 13:03:21.822 [info] Set config option 'zig_exe_path' to "/home/gabe/.zvm/bin/zig"
2025-07-19 13:03:21.822 [info] Set config option 'build_runner_path' to "/home/gabe/.cache/zls/build_runner/1d53bc737952080cbb4ceac8f3674c20/build_runner.zig"
2025-07-19 13:03:21.822 [info] Set config option 'global_cache_path' to "/home/gabe/.cache/zls"
2025-07-19 13:03:21.827 [info] Loaded build file 'file:///home/gabe/Code/zig/build.zig'
2025-07-19 13:03:22.452 [error] error (default): ParseError
2025-07-19 13:03:22.452 [error] Server process exited with code 1.
2025-07-19 13:03:22.453 [info] Connection to server got closed. Server will restart.
2025-07-19 13:03:22.459 [info] Starting ZLS      0.15.0-dev.293+45b855f7 @ '/home/gabe/.config/Code - OSS/User/globalStorage/ziglang.vscode-zig/zls/x86_64-linux-0.15.0-dev.293+45b855f7/zls'
2025-07-19 13:03:22.459 [info] Log File:         /home/gabe/.cache/zls/zls.log (info)
2025-07-19 13:03:22.459 [info] Client Info:      Code - OSS (1.101.1)
2025-07-19 13:03:22.460 [info] Autofix Mode:     'source.fixall'
2025-07-19 13:03:22.460 [info] added Workspace Folder: file:///home/gabe/Code/zig
2025-07-19 13:03:22.466 [info] Set config option 'builtin_path' to "/home/gabe/.cache/zls/builtin.zig"
2025-07-19 13:03:22.466 [info] Set config option 'zig_lib_path' to "/home/gabe/.zvm/master/lib"
2025-07-19 13:03:22.466 [info] Set config option 'zig_exe_path' to "/home/gabe/.zvm/bin/zig"
2025-07-19 13:03:22.466 [info] Set config option 'build_runner_path' to "/home/gabe/.cache/zls/build_runner/1d53bc737952080cbb4ceac8f3674c20/build_runner.zig"
2025-07-19 13:03:22.466 [info] Set config option 'global_cache_path' to "/home/gabe/.cache/zls"
2025-07-19 13:03:22.471 [info] Loaded build file 'file:///home/gabe/Code/zig/build.zig'
2025-07-19 13:03:23.055 [error] error (default): ParseError
2025-07-19 13:03:23.055 [error] Server process exited with code 1.
2025-07-19 13:03:23.056 [info] Connection to server got closed. Server will restart.
2025-07-19 13:03:23.061 [info] Starting ZLS      0.15.0-dev.293+45b855f7 @ '/home/gabe/.config/Code - OSS/User/globalStorage/ziglang.vscode-zig/zls/x86_64-linux-0.15.0-dev.293+45b855f7/zls'
2025-07-19 13:03:23.061 [info] Log File:         /home/gabe/.cache/zls/zls.log (info)
2025-07-19 13:03:23.061 [info] Client Info:      Code - OSS (1.101.1)
2025-07-19 13:03:23.061 [info] Autofix Mode:     'source.fixall'
2025-07-19 13:03:23.061 [info] added Workspace Folder: file:///home/gabe/Code/zig
2025-07-19 13:03:23.067 [info] Set config option 'builtin_path' to "/home/gabe/.cache/zls/builtin.zig"
2025-07-19 13:03:23.067 [info] Set config option 'zig_lib_path' to "/home/gabe/.zvm/master/lib"
2025-07-19 13:03:23.067 [info] Set config option 'zig_exe_path' to "/home/gabe/.zvm/bin/zig"
2025-07-19 13:03:23.067 [info] Set config option 'build_runner_path' to "/home/gabe/.cache/zls/build_runner/1d53bc737952080cbb4ceac8f3674c20/build_runner.zig"
2025-07-19 13:03:23.067 [info] Set config option 'global_cache_path' to "/home/gabe/.cache/zls"
2025-07-19 13:03:23.072 [info] Loaded build file 'file:///home/gabe/Code/zig/build.zig'
2025-07-19 13:03:23.642 [error] error (default): ParseError
2025-07-19 13:03:23.643 [error] Server process exited with code 1.
2025-07-19 13:03:23.643 [info] Connection to server got closed. Server will restart.
2025-07-19 13:03:23.649 [info] Starting ZLS      0.15.0-dev.293+45b855f7 @ '/home/gabe/.config/Code - OSS/User/globalStorage/ziglang.vscode-zig/zls/x86_64-linux-0.15.0-dev.293+45b855f7/zls'
2025-07-19 13:03:23.649 [info] Log File:         /home/gabe/.cache/zls/zls.log (info)
2025-07-19 13:03:23.649 [info] Client Info:      Code - OSS (1.101.1)
2025-07-19 13:03:23.649 [info] Autofix Mode:     'source.fixall'
2025-07-19 13:03:23.649 [info] added Workspace Folder: file:///home/gabe/Code/zig
2025-07-19 13:03:23.655 [info] Set config option 'builtin_path' to "/home/gabe/.cache/zls/builtin.zig"
2025-07-19 13:03:23.655 [info] Set config option 'zig_lib_path' to "/home/gabe/.zvm/master/lib"
2025-07-19 13:03:23.655 [info] Set config option 'zig_exe_path' to "/home/gabe/.zvm/bin/zig"
2025-07-19 13:03:23.655 [info] Set config option 'build_runner_path' to "/home/gabe/.cache/zls/build_runner/1d53bc737952080cbb4ceac8f3674c20/build_runner.zig"
2025-07-19 13:03:23.655 [info] Set config option 'global_cache_path' to "/home/gabe/.cache/zls"
2025-07-19 13:03:23.660 [info] Loaded build file 'file:///home/gabe/Code/zig/build.zig'
2025-07-19 13:03:24.250 [error] error (default): ParseError
2025-07-19 13:03:24.250 [error] Server process exited with code 1.
2025-07-19 13:03:24.251 [error] The ZLS language server server crashed 5 times in the last 3 minutes. The server will not be restarted. See the output for more information.

[The-Briel-Deal]

I might see if I can debug and solve this a little later, but I figured I would still create the ticket so that it's a known issue (:

[The-Briel-Deal]

I also just tried using zls 0.14.0 and it works perfect on this file. I'll see if I can bisect for the commit later.

[xdBronch]

i ran into this as well, should be fixed by ziglang/zig#24501 or moving to a pre-writergate version of zig and zls

[Techatrix]

This is the issue that ziglang/zig#24501 is trying to fix. The latest update to zigtools/lsp-kit should also resolve this issue without requiring that PR.

[Techatrix]

fixed by 09e8cd6.

[The-Briel-Deal]

Ty Techatrix! That was quick!