$OpenBSD: patch-tools_build_src_engine_execunix_c,v 1.2 2020/08/15 20:30:40 rsadowski Exp $

Index: tools/build/src/engine/execunix.c
--- tools/build/src/engine/execunix.c.orig
+++ tools/build/src/engine/execunix.c
@@ -503,6 +503,7 @@ void exec_wait()
             sigemptyset(&sigmask);
             sigaddset(&sigmask, SIGCHLD);
             sigprocmask(SIG_BLOCK, &sigmask, NULL);
+if (select_timeout == 0) select_timeout++;
             while ( ( ret = poll( wait_fds, WAIT_FDS_SIZE, select_timeout * 1000 ) ) == -1 )
                 if ( errno != EINTR )
                     break;
