llvm_libcxx/regex_ECMAScript: Crash in std::__1::__back_ref<char>::__exec

Detailed report: https://oss-fuzz.com/testcase?key=6590682782236672 Project: llvmlibcxx Fuzzer: libFuzzerllvmlibcxxregexECMAScript Fuzz target binary: regexECMAScript Job Type: libfuzzerasanllvmlibcxx Platform Id: linux Crash Type: UNKNOWN READ Crash Address: 0x00037fff7fff Crash State:...