#1 Linux: @cImport requires compiling with "--library c"

[Joshua Haberman]

When I try compiling the "Zig code only" example in the readme, I get the following error:

cmd zig build-lib -dynamic -DPYHEXVER=50857712 --name zig_sum.cpython-38-x86_64-linux-gnu -I /usr/include/python3.8 -I /usr/include sum.zig
./sum.zig:3:11: error: C import failed
const c = @cImport({
          ^
./sum.zig:3:11: note: libc headers not available; compilation does not link against libc
const c = @cImport({

This is fixed by passing --library c to the command-line of zig build-lib.

[Joshua Haberman]

I was able to solve this with the following patch:

diff -r 85a4f0350abb setuptools_zig.py
--- a/setuptools_zig.py Fri Dec 04 22:16:55 2020 +0100
+++ b/setuptools_zig.py Sun Mar 21 15:16:38 2021 -0700
@@ -29,7 +29,7 @@
         target = Path(self.get_ext_fullpath(ext.name))

         zig = os.environ.get('PY_ZIG', 'zig')  # override zig in path with specific version
-        bld_cmd = [zig, 'build-lib', '-dynamic', '-DPYHEXVER={}'.format(sys.hexversion), '--name', output.stem]
+        bld_cmd = [zig, 'build-lib', '-dynamic', '-DPYHEXVER={}'.format(sys.hexversion), '--name', output.stem, '--library', 'c']
         for inc_dir in self.compiler.include_dirs:
             bld_cmd.extend(('-I', inc_dir))
         bld_cmd.extend(('-I', '/usr/include'))