we can build musl with zig cc too, don't need musl toolchain

src/SPC/builder/unix/library/attr.php

@@ -15,6 +15,9 @@ trait attr
     protected function build(): void
     {
         UnixAutoconfExecutor::create($this)
+            ->appendEnv([
+                'CFLAGS' => '-Wno-int-conversion -Wno-implicit-function-declaration',
+            ])
             ->exec('libtoolize --force --copy')
             ->exec('./autogen.sh || autoreconf -if')
             ->configure('--disable-nls')