Index: libcfa/src/concurrency/kernel.cfa
===================================================================
--- libcfa/src/concurrency/kernel.cfa	(revision 26ffcda7be19956079f749581cbc5686b444a78b)
+++ libcfa/src/concurrency/kernel.cfa	(revision dab09ad17d681d164e04da583cd9bde8fb8e96ff)
@@ -532,4 +532,6 @@
 		unsigned total   = this.total;
 		processor * proc = &this.list`first;
+		// Thread fence is unnecessary, but gcc-8 and older incorrectly reorder code without it
+		__atomic_thread_fence(__ATOMIC_SEQ_CST);
 		if(l != __atomic_load_n(&this.lock, __ATOMIC_SEQ_CST)) { Pause(); continue; }
 		return [idle, total, proc];