diff --git a/src/haproxy.c b/src/haproxy.c
index 125f082..b94252d 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -1370,7 +1370,7 @@
 
 	if (global.rlimit_memmax) {
 		limit.rlim_cur = limit.rlim_max =
-			global.rlimit_memmax * 1048576 / global.nbproc;
+			global.rlimit_memmax * 1048576ULL / global.nbproc;
 #ifdef RLIMIT_AS
 		if (setrlimit(RLIMIT_AS, &limit) == -1) {
 			Warning("[%s.main()] Cannot fix MEM limit to %d megs.\n",