On Tue, Dec 2, 2025 at 4:56 PM Bruno Haible via Gnulib discussion list <[email protected]> wrote: > > I wrote: > > The buggy commit is FreeBSD commit e19d46c808267f53455e96a28ff7654211523d2c. > > One can also say that the buggy commit is > 90253d49db09a9b1490c448d05314f3e4bbfa468. > > The reproducer crashes at the instruction > movdqa 0x10(%rsi),%xmm0 > at line 230 of src/lib/libc/amd64/string/stpncpy.S.
If the code is changed from an aligned load (movdqa) to a non-aligned load (movdqu), the problem will likely go away. It is easier than trying to get the compiler to use a non-aligned string with fixups and casts. In the old days there might be a small performance gain by using aligned words and movdqa. Nowaday it is not worth it for most cases. Jeff
