On Sat, 15 Feb 2025 21:30:16 +0000 Sam James <s...@gentoo.org> wrote:
> > + * This stand-in for std::regex was written because the > > implementation provided > > + * by the GCC libstdc++ in GCC 11 proved too slow, where "slow" > > means "appears > > + * not to terminate". Some invocations of std::regex_search took > > over 5 > > Is this still the case now in GCC trunk (15)? Is there a bug report to > link to in the comment if so? I didn't pursue a bug report for this problem, so as not to try to boil the ocean. AFAIK, the poor performance of std::regex is widely acknowledged and is somehow a feature of how it's defined. Jonathan Wakely understands the problem better than I do. Although under no obligation to use std::regex, I thought I'd try it out and, honestly, it's not a bad interface. But the performance was awful. It was easy to re-implement what I needed from std::regex in terms of regex(3), and left the door open to revert simply by changing "using namespace dts". Is the state of gcc-15 relevant, though? gcc is frequently built using whatever C++ compiler is installed. If my understanding is correct, to rely on the installed std::regex is just to set a trap for the user. --jkl
