Assign properties to dispatch_queue_attr_concurrent on Linux

Author: seabaylea

src/init.c

@@ -260,6 +260,21 @@ const struct dispatch_queue_attr_s _dispatch_queue_attrs[]
 	DISPATCH_QUEUE_ATTR_QOS_INITIALIZER(USER_INTERACTIVE),
 };
 
+#ifndef __APPLE__
+// _dispatch_queue_attr_concurrent is only aliased on Darwin where the
+// -alias_list linker option exists. On other platforms we need to assign
+// the structure and properties directly.
+struct dispatch_queue_attr_s _dispatch_queue_attr_concurrent = {
+	.do_vtable = DISPATCH_VTABLE(queue_attr),
+	.do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
+	.do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
+	.do_next = DISPATCH_OBJECT_LISTLESS,
+	.dqa_qos_class = _DISPATCH_QOS_CLASS_UNSPECIFIED,
+	.dqa_relative_priority = 0,
+	.dqa_overcommit = _dispatch_queue_attr_overcommit_unspecified,
+	.dqa_concurrent = 1
+};
+#endif
 
 #pragma mark -
 #pragma mark dispatch_vtables