Update zlib-ng to 2.1.3

[JakubOnderka]

zlib-ng 2.1.2 is the first stable release of the 2.1.x branch.

Most important optimizations and Enhancements:

• Decompression is a lot faster (56% faster measured on AVX2-capable x86-64)
• Compresson is improved for Level 9, at the cost of a little performance.
• Compression is improved for Level 3, by switching from deflate_fast to deflate_medium.

Full changelog

[JohnTitor]

Hm, I'm not sure if it's the fault of ctest but CI fails:

  D:\a\libz-sys\libz-sys\target\x86_64-pc-windows-msvc\debug\build\systest-zng-5622f69de174c92e\out\all.c(1295): warning C4047: 'return': 'int (__cdecl *)(zng_streamp,int,const char *,int)' differs in levels of indirection from 'int'
  D:\a\libz-sys\libz-sys\target\x86_64-pc-windows-msvc\debug\build\systest-zng-5622f69de174c92e\out\all.c(1300): error C2065: 'zng_deflateInit2_': undeclared identifier
  D:\a\libz-sys\libz-sys\target\x86_64-pc-windows-msvc\debug\build\systest-zng-5622f69de174c92e\out\all.c(1300): warning C4047: 'return': 'int (__cdecl *)(zng_streamp,int,int,int,int,int,const char *,int)' differs in levels of indirection from 'int'
  D:\a\libz-sys\libz-sys\target\x86_64-pc-windows-msvc\debug\build\systest-zng-5622f69de174c92e\out\all.c(1350): error C2065: 'zng_inflateBackInit_': undeclared identifier
  D:\a\libz-sys\libz-sys\target\x86_64-pc-windows-msvc\debug\build\systest-zng-5622f69de174c92e\out\all.c(1350): warning C4047: 'return': 'int (__cdecl *)(zng_streamp,int,unsigned char *,const char *,int)' differs in levels of indirection from 'int'
  D:\a\libz-sys\libz-sys\target\x86_64-pc-windows-msvc\debug\build\systest-zng-5622f69de174c92e\out\all.c(1370): error C2065: 'zng_inflateInit_': undeclared identifier
  D:\a\libz-sys\libz-sys\target\x86_64-pc-windows-msvc\debug\build\systest-zng-5622f69de174c92e\out\all.c(1370): warning C4047: 'return': 'int (__cdecl *)(zng_streamp,const char *,int)' differs in levels of indirection from 'int'
  D:\a\libz-sys\libz-sys\target\x86_64-pc-windows-msvc\debug\build\systest-zng-5622f69de174c92e\out\all.c(1375): error C2065: 'zng_inflateInit2_': undeclared identifier
  D:\a\libz-sys\libz-sys\target\x86_64-pc-windows-msvc\debug\build\systest-zng-5622f69de174c92e\out\all.c(1375): warning C4047: 'return': 'int (__cdecl *)(zng_streamp,int,const char *,int)' differs in levels of indirection from 'int'

[Byron]

Thanks for the update! I am quite new here and am as puzzled as you why these symbols would go missing all of the sudden. Is this something that reproduces locally?

[JakubOnderka]

Build tests fixed, but I am not 100 % sure if everything is correct. Can you please check it before merging?

[Byron]

Thanks so much!

CI is happy now and I wonder if that's all we need. Maybe there is other (avoidable) compatibility problems that arise when this crate is used by flate2 or other major dependents? It seems only manual testing can show what would happen, and I'd be satisfied knowing that flate2 still works with this version of the crate, or that we are not missing anything here to maintain compatibility.

[thaliaarchi]

FYI, zlib-ng 2.1.3, which has now been released, is also marked as stable.

[Byron]

I'd be the first to want to merge this, and it all looks good to me, but that doesn't mean much.
Could I have another set of eyes?

[Byron]

I decided to fix my one issue, which was running tests through flate2. It turned out that what's on main doesn't actually compile for me, at least not on MacOS, whereas this branch works just fine. All flate2 tests pass, and I wonder if I should adjust the CI to test libz-sys and libz-ng-sys with the latest version of flate2 as well.

That way we could be more confident that nothing is broken, at least according to one of the main consumers of this crate.

In any case, I'd be willing to merge now.

[Byron]

With the additional testing in 5f2cf8d it turns out that what's in this PR is actually working with flate2, whereas what's in main causes failures with zlib-ng and zlib-ng-compat due to memory corruption.

Thus I will merge this PR now and see that I create a new point release.

[Byron]

A new release was published.