diff --git a/tests/compat.sh b/tests/compat.sh
index 0eae1ea..80c2d31 100755
--- a/tests/compat.sh
+++ b/tests/compat.sh
@@ -15,6 +15,10 @@
 
 set -u
 
+# Limit the size of each log to 10 GiB, in case of failures with this script
+# where it may output seemingly unlimited length error logs.
+ulimit -f 20971520
+
 # initialise counters
 TESTS=0
 FAILED=0