correct libc name for linux

src/SPC/builder/linux/LinuxBuilder.php

@@ -52,7 +52,7 @@ public function __construct(array $options = [])
 
         // ---------- set necessary compile environments ----------
         // set libc
-        $this->libc = 'musl'; // SystemUtil::selectLibc($this->cc);
+        $this->libc = $this->getOption('cc', 'gcc') === 'musl-gcc' ? 'musl_wrapper' : 'musl'; // SystemUtil::selectLibc($this->cc);
         // concurrency
         $this->concurrency = SystemUtil::getCpuCount();
         // cflags