Please provide Libs.private in the .pc for static link

[yurivict]

pkg-config --static --libs libzstd should return the .a library, like this ``/usr/local/lib/libzstd.a```
For this .pc file should contain such line:

Libs.private: ${libdir}/libzstd.a

[nmathewson]

This issue is a blocker for Tor building statically with zstd support; see also https://trac.torproject.org/projects/tor/ticket/22550

[nmathewson]

I think the diagnosis above may be incorrect, however. The Libs.private line is supposed to contain the list of libraries used by the static library, not the library itself.

[terrelln]

@nmathewson libzstd doesn't have any dependencies by default. There is an option to enable multithreaded compression support, but it isn't enabled by default yet.

[yurivict]

It seems from the web search that pkgconfig is broken on the conceptual level, because it doesn't allow static library detection. I didn't realize this when I wrote the OP.

You should develop the cmake module instead, as cmake seems to be more conceptually sound.

[Cyan4973]

Here is what I could gather regarding Links.private :
https://people.freedesktop.org/~dbn/pkg-config-guide.html

Libs.private: The link flags for private libraries required by this package but not exposed to applications.

It seems unrelated to your issue (build statically with zstd).
Maybe we need another solution

[yurivict]

Maybe we need another solution

It doesn't appear that .pc can be fixed for the static build. One option is to have two .pc files: zstd.pc and zstd-static.pc.

Tor IMO should use autotools instead of pkgconfig in this instance.

[yurivict]

I think I misdiagnosed the problem. /usr/local/lib/libzstd.a is stripped when installed from the centrally built package for some reason. This is why tor failed, not because of pkg-config.