Below is the error that I get. FWIW, using #include <header> is not ideal, it should be #include "header" but seems to be not what Zig’s doing.
But I was able to fix it too. In my case, I have split my project into “utils” (lib) package and “main” (exe). I had added the include path for “utils” with lib.addIncludePath("src/gfxutil/"). With just this, building main exe fails as below. But if I also add exe.addIncludePath("src/gfxutil/") to the exe build options, it works. This is a little surprising, I would’ve expected it to be enough to specify the include path only for the library I’m building and that’d be enough. It’s probably not working as intended…?
src\gfxutil\joystick.zig:3:12: error: C import failed
const c2 = @cImport({
^~~~~~~~
referenced by:
initJoystick: src\gfxutil\joystick.zig:9:5
init: src\main.zig:267:21
remaining reference traces hidden; use '-freference-trace' to see all reference traces
<snip>\67da55fd196b7c4b10285f836db20262\cimport.h:1:10: error: 'joystick.h' file not found
#include <joystick.h>
^