https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103755
--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Jonathan Wakely from comment #3) > Created attachment 52025 [details] > Alternative implementation v2 > > The diagnostic regression is easy to fix with a static assertion before > calling __try_use_facet. Although that causes errors for certain uses of streams without including <locale>, specifically when building the library. Also I forgot to say that I can still reproduce approx. 3x speedup using my patch. Before: BM_sstream_construct 288 ns 287 ns 2525913 BM_fstream_construct 319 ns 318 ns 2204065 After: BM_sstream_construct 99.5 ns 99.1 ns 6512679 BM_fstream_construct 108 ns 107 ns 6536463
