diff --git a/run_tests_asan.sh b/run_tests_asan.sh
index ae5ad18..84fa624 100644
--- a/run_tests_asan.sh
+++ b/run_tests_asan.sh
@@ -4,6 +4,5 @@ rm ./tests_executable_asan
 # compile with AddressSanitizer to catch memory-safety regressions (e.g. new/free mismatches, use-after-free)
 g++ -fsanitize=address -g src/*.cpp -o tests_executable_asan
 
-# run executable (leak detection is off: a pre-existing, separately tracked leak
-# in the throw-by-pointer exception pattern would otherwise fail every run)
-ASAN_OPTIONS=detect_leaks=0 ./tests_executable_asan
+# run executable (leak detection is on, so an unfreed allocation fails the run)
+ASAN_OPTIONS=detect_leaks=1 ./tests_executable_asan