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   Ivan Molodetskikh (yalter@mastodon.online)'s status on Tuesday, 30-Dec-2025 17:43:06 JST Ivan Molodetskikh

   One thing I'm missing in the Rust ecosystem of bindings to C libraries is easy conditional compilation based on the build-time library version. Something like the GTK_CHECK_VERSION() macros in C.

   In Rust bindings, it's common to expose some baseline version API, then have feature flags to expose (and depend on) newer versions of the library. But there's no simple way to do, as a downstream user:

   #[cfg(have_gtk_4_12)]
   use_new_api();
   #[cfg(not(have_gtk_4_12))]
   fallback_with_old_api();

   #rust

   • Embed this notice
     Janneke (janneke@todon.nl)'s status on Tuesday, 30-Dec-2025 17:43:04 JST Janneke

     in reply to

     • MortSinyx

     @YaLTeR @cnx
     Of course, even when one bit changes.

   • Embed this notice
     MortSinyx (cnx@awkward.place)'s status on Tuesday, 30-Dec-2025 17:43:05 JST MortSinyx

     in reply to
     @YaLTeR, Nix and Guix handles this by rebuilding dependents whenever one of their dependency changes.
   • Embed this notice
     Ivan Molodetskikh (yalter@mastodon.online)'s status on Tuesday, 30-Dec-2025 17:43:05 JST Ivan Molodetskikh

     in reply to

     • MortSinyx

     @cnx even on minor bumps?

   • Embed this notice
     Ivan Molodetskikh (yalter@mastodon.online)'s status on Tuesday, 30-Dec-2025 17:43:06 JST Ivan Molodetskikh

     in reply to

     Related: how do distros track these build-time dependency checks? E.g. my app did a build-time check and used the GTK < 4.12 code path, then the distro updated GTK to 4.12, so now my app needs to be rebuilt to take advantage of the new API. How is this tracked?

     I guess this question is more relevant for rolling-release distros, but it's very possible for a build-time check to test for a minor version which would be updated even in a non-rolling-release distro.

     #linux #fedora