diff --git a/ghc/tests/concurrent/should_run/Makefile b/ghc/tests/concurrent/should_run/Makefile
index fb804f0b4e840442826c294ee1fed8b47afb74bd..c60df67a1415d975bf0b37f0f7dc3a95157a0509 100644
--- a/ghc/tests/concurrent/should_run/Makefile
+++ b/ghc/tests/concurrent/should_run/Makefile
@@ -1,11 +1,12 @@
 #-----------------------------------------------------------------------------
-# $Id: Makefile,v 1.4 2000/03/21 15:54:25 simonmar Exp $
+# $Id: Makefile,v 1.5 2000/04/26 10:03:28 simonmar Exp $
 
 TOP = ../..
 include $(TOP)/mk/boilerplate.mk
 include $(TOP)/mk/should_run.mk
 
 conc009_RUNTEST_OPTS = -x 1
+conc021_RUNTEST_OPTS = -x 250
 
 SRC_HC_OPTS += -dcore-lint -syslib concurrent -fglasgow-exts
 
diff --git a/ghc/tests/concurrent/should_run/conc021.hs b/ghc/tests/concurrent/should_run/conc021.hs
new file mode 100644
index 0000000000000000000000000000000000000000..6d3fe0a540ce3319b96f554628a60c0694576aaa
--- /dev/null
+++ b/ghc/tests/concurrent/should_run/conc021.hs
@@ -0,0 +1,3 @@
+module PrelMain where
+
+mainIO = error "wurble"
diff --git a/ghc/tests/concurrent/should_run/conc021.stderr b/ghc/tests/concurrent/should_run/conc021.stderr
new file mode 100644
index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391