Try putting ulimit -c 0 in test_bt.sh to see if it fixes bug 26787

src/test/test_bt.sh

@@ -3,6 +3,8 @@
 
 exitcode=0
 
+ulimit -c 0
+
 export ASAN_OPTIONS="handle_segv=0:allow_user_segv_handler=1"
 "${builddir:-.}/src/test/test-bt-cl" backtraces || exit $?
 "${builddir:-.}/src/test/test-bt-cl" assert 2>&1 | "${PYTHON:-python}" "${abs_top_srcdir:-.}/src/test/bt_test.py" || exitcode="$?"