diff --git a/include/common/hathreads.h b/include/common/hathreads.h
index 82357d5..95dfb05 100644
--- a/include/common/hathreads.h
+++ b/include/common/hathreads.h
@@ -170,7 +170,7 @@
 	ti = &ha_thread_info[tid];
 }
 
-static inline unsigned long ha_get_pthread_id(unsigned int thr)
+static inline unsigned long long ha_get_pthread_id(unsigned int thr)
 {
 	return 0;
 }
diff --git a/src/debug.c b/src/debug.c
index a94fd28..efbf19f 100644
--- a/src/debug.c
+++ b/src/debug.c
@@ -58,7 +58,7 @@
 	int stuck = !!(ha_thread_info[thr].flags & TI_FL_STUCK);
 
 	chunk_appendf(buf,
-	              "%c%cThread %-2u: id=0x%lx act=%d glob=%d wq=%d rq=%d tl=%d tlsz=%d rqsz=%d\n"
+	              "%c%cThread %-2u: id=0x%llx act=%d glob=%d wq=%d rq=%d tl=%d tlsz=%d rqsz=%d\n"
 	              "             stuck=%d prof=%d",
 	              (thr == calling_tid) ? '*' : ' ', stuck ? '>' : ' ', thr + 1,
 		      ha_get_pthread_id(thr),