expr:fuzz_expr: Crash with empty stacktrace

Detailed Report: https://oss-fuzz.com/testcase?key=4660506639007744 Project: expr Fuzzing Engine: libFuzzer Fuzz Target: fuzzexpr Job Type: libfuzzerasanexpr Platform Id: linux Crash Type: UNKNOWN READ Crash Address: 0xfffffffffffffff0 Crash State: NULL Sanitizer: address ASAN Recommended Securit...