diff --git a/ci_test.sh b/ci_test.sh
index c624724..035f896 100755
--- a/ci_test.sh
+++ b/ci_test.sh
@@ -6,7 +6,14 @@ sudo dpkg -i ../comcom64*.deb
 
 . ./ci_test_prereq.sh
 
-dosemu -td -E ver
+if ! dosemu -td -o boot.log -E ver ; then
+  {
+    echo "================== boot.log ==================="
+    cat boot.log
+    echo "==============================================="
+  } >&2
+  exit 1
+fi
 
 make 32 -j 9
 # make sure 32bit version also built