Import Lib generation and path on windows

[Selemba1000]

Zig Version

0.15.1

Steps to Reproduce and Observed Behavior

I am currently developing some tooling to support one of my use-cases where i combine Zig and the JVM. That usually means compiling zig code to dynamic libraries and loading them dynamically on the JVM. But my problem is not specific to this use-case, just as a background story.

I noticed when compiling a dynamic library for a windows target, zig by default generates a import library. Emition of the ImpLib can be adjusted via the --fno-emit-implib Flag for zig build-lib, but i have not found a way of doing the same with zig build. Maybe i missed it, but if it's not present yet i think it would be good to have.

During my testing i also stumbled onto another weird behavior. The generated import lib gets placed in the lib folder inside the zig-out directory. But the actual dll file gets placed in the bin directory together with generated binaries. I don't know if this is on purpose, but it makes it extra difficult for me. I need to process the compiled libraries afterwards, so i need to add a uncomfortable hack to find the correct library depending on the platform. It is also kinda counter-intuitive to have the dynamic library in the folder for executables.

Expected Behavior

Ideally i would have a flag in the addLibrary options, or in some other options struct, to control the generation of ImpLib. It would also be nice if i could disable pdb generation in the same spot. I don't think any of those files are actually useful for importing via FFI. But they are good to have for developers that want to import in a more c way. I think a configuration, like is already present in build-lib, is the right option, but im open for suggestions.

For the paths I feel like placing everything in the lib folder that is related to libraries is the best option. But I am not sure what uses the current mapping might have, so please discuss.

[BraynStorm]

You can get the path to the implib like this - dll.getEmittedImplib(). This gives you a LazyPath, and then you can use b.addInstall*(implib_path, .{ ... }); and configure it how you'd like.

Same for the PDB, you can just give it a .pdb = .disabled when installing the artifact, AFAIK.

[squeek502]

Relevant links:

• Inconsistent output of shared libraries on different operating systems #22334 (comment)
• std.Build: Install Windows DLLs to <prefix>/bin/ by default #19743

For customizing or disabling import library installation, you can use the field implib_dir in Step.InstallArtifact.Options during b.addInstallArtifact, e.g. .implib_dir = .disabled or .implib_dir = .{ .override = .bin } (or .dest_dir = .{ .override = .lib } if you want the dll to be installed to lib).

Let me know if that adequately addresses your use case.

[Selemba1000]

Thanks for letting me know. That is plenty to get it to work. I just totally missed those configuration options. I think it would be nice to have some documentation on this, but considering zig guide is also outdated already, im guessing it's already planned and just not done yet.

Thanks for the replies and zig in general. Keep up the good work.

[squeek502]

No problem. In the future, it would be good to run stuff like this by one of the community spaces before using the issue tracker.