I am using undefined behaviour sanitizers and they are detecting a potential bug in teh regex header, the specific report is: `/usr/include/c++/11/bits/regex.h:909:15: runtime error: load of value 192, which is not a valid value for type 'bool'` Which does seem like the use of a potentially uninitialized boolean.
std::sub_match only has one constructor, and it initializes the bool. The only stores to that variable are literal treu or false values, or the result of a boolean expression first != last. So there's no way I can see for the library to cause this behaviour Are you sure you're not causing undefined behaviour in your own code? Have you tried building with -D_GLIBCXX_DEBUG to get runtime checks in std::match_results. Without more details there's nothing we can do here. The <regex> code looks correct.
No feedback or a testcase in over 2 years so closing as invalid. If you provide a testcase we will be able to look into it but until then, closing as invalid.