diff --git a/mps/home/bin/build/MM_src_trunk b/mps/home/bin/build/MM_src_trunk
index 8a267e9193e..23cfed1dd7f 100644
--- a/mps/home/bin/build/MM_src_trunk
+++ b/mps/home/bin/build/MM_src_trunk
@@ -2,7 +2,7 @@
 #
 # Build and test MM at tip of main trunk (the MM_src compound)
 # 
-# $HopeName: HOMEmm!bin:build:MM_src_trunk(trunk.11) $
+# $HopeName: HOMEmm!bin:build:MM_src_trunk(trunk.12) $
 #
 
 script="`basename $0`"
@@ -31,21 +31,20 @@ hope co -compound MM -branch . -recursive \
 
 cd mm/src &&
 
-# # commented out but not deleted for pedagogical reasons
-# # (you might one day want to build a library)
 for lib in mps.a
 do
   gnumake -r -f sus8gc.gmk $lib ||
     die "Unable to build library $lib of trunk"
-done
+done &&
 
 for test in amcss dwstress lockcov locv mpmss mpsicv poolncv \
             qs mpmconft finalcv
 do
-  gnumake -r -f sus8gc.gmk $test &&
+  gnumake -r -f sus8gc.gmk $test ||
+    die "Unable to build test $test of trunk"
   for variety in hi ci ti
   do
     ./sus8gc/$variety/$test ||
-      die "Unable to build and run test $test of trunk"
+      die "Failed test $variety/$test of trunk"
   done
 done