stdio.h breaks build

[CamJN]

Crate name

getargv-sys

Build failure link

https://docs.rs/crate/getargv-sys/0.5.8/builds/2359247/x86_64-apple-darwin.txt

Additional details

My crate uses bindgen to create rust bindings in build.rs by converting wrapper.h.

However recently it has started to break the docs build with errors in stdio.h which wrapper.h includes.

[INFO] [stderr]   /usr/include/stdio.h:184:35: error: expected ';' after top level declarator
[INFO] [stderr]   /usr/include/stdio.h:184:48: error: expected identifier or '('
[INFO] [stderr]   /usr/include/stdio.h:184:48: error: expected ')'
[INFO] [stderr]   /usr/include/stdio.h:184:47: note: to match this '('

[CamJN]

Looking at /usr/include/stdio.h line 184 in the rustops/crates-build-env:latest docker image looks like this:

   181	
   182	#ifdef __USE_LARGEFILE64
   183	extern FILE *tmpfile64 (void) __wur;
   184	#endif
   185	

which doesn't have 35 characters, let alone 48.

[syphar]

Hi,

you can find the build image here, created from this repo.

Can you check how it looks there?

More info on the build process also here: https://docs.rs/about/builds

Since your build failure is from the darwin build, is it possible the issue is that we only can use cross compilation and currently can't build natively on darwin?

The classic solution for cases like this (if I'm right) is to use conditional compilation (via a feature & docs.rs metadata, #[cfg(docsrs)] or the DOCS_RS environment variable) to make your docs build without the system dependency. Often the public interface of your crate doesn't expose parts of the used C API.

[CamJN]

Often the public interface of your crate doesn't expose parts of the used C API.

The crate is a -sys bindings crate, that's exactly what it does.

make your docs build without the system dependency.

It's using stdio.h for struct FILE and size_t, I can shim them out, but it seems like pretty basic stuff that should work.

Line 184 of /usr/include/stdio.h in the image is extern int fclose (FILE *__stream) __nonnull ((1)); which does look weird.