On Mon, Jun 23, 2025 at 10:51:21AM -0400, Tom Lane wrote: > This has broken the build completely on my RHEL8 x86_64 box, > with gcc 8.5.0: > > $ ./configure ... > $ make -s > pg_crc32c_sse42.c: In function 'pg_comp_crc32c_avx512': > pg_crc32c_sse42.c:126:25: warning: implicit declaration of function > '_mm512_zextsi128_si512'; did you mean '_mm512_castsi128_si512'? > [-Wimplicit-function-declaration] > x0 = _mm512_xor_si512(_mm512_zextsi128_si512(_mm_cvtsi32_si128(crc0)), x0); > ^~~~~~~~~~~~~~~~~~~~~~ > _mm512_castsi128_si512
It looks like thse weren't added until GCC 10 [0]. > I see similar symptoms on buildfarm animal conchuela, which > is DragonFly BSD of some vintage or other. Not sure why > more animals aren't complaining. Anyway, it seems that the > configure probe to see if this facility is available had > better be adjusted to match the new code. Unfortunately, this will probably require more than replacing _mm512_castsi512_si128 with _mm512_zextsi512_si128 because the latter doesn't exist. [0] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83250 -- nathan
