Testing a current coreutils with a current gnulib on CentOS 8 and
CentOS 8 Stream, I see the same compilation error on both:
CC src/libcksum_avx512_a-cksum_avx512.o
../src/cksum_avx512.c: In function 'cksum_avx512':
../src/cksum_avx512.c:60:22: warning: implicit declaration of function
'_mm512_set_epi8'; did you mean '_mm512_set1_epi8'?
[-Wimplicit-function-declaration]
shuffle_constant = _mm512_set_epi8 (0, 1, 2, 3, 4, 5, 6, 7, 8,
^~~~~~~~~~~~~~~
_mm512_set1_epi8
../src/cksum_avx512.c:60:20: error: incompatible types when assigning to type
'__m512i' {aka '__vector(8) long long int'} from type 'int'
shuffle_constant = _mm512_set_epi8 (0, 1, 2, 3, 4, 5, 6, 7, 8,
^
make[2]: *** [Makefile:20396: src/libcksum_avx512_a-cksum_avx512.o] Error 1
The cause is that USE_AVX512_CRC32 was determined to be true at configure
time, although the compiler does not support all builtin functions used
by cksum_avx512.c.
This proposed patch fixed it. I verified that on Ubuntu 24.04 and
CentOS Stream 9, USE_AVX512_CRC32 remains true.
>From 9f00e68762c9457c8ef7e8fd90db102e5281de72 Mon Sep 17 00:00:00 2001
From: Bruno Haible <[email protected]>
Date: Thu, 16 Jan 2025 22:10:26 +0100
Subject: [PATCH] build: Fix compilation error on CentOS 8 Stream
* configure.ac (USE_AVX512_CRC32): Set to false if the function
_mm512_set_epi8 does not exist.
---
configure.ac | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/configure.ac b/configure.ac
index e3c8f4c30..bf6da2a5a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -727,6 +727,10 @@ AC_LINK_IFELSE(
main (void)
{
__m512i a, b;
+ a = _mm512_set_epi8 (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
a = _mm512_clmulepi64_epi128 (a, b, 0x00);
a = _mm512_shuffle_epi8 (a, b);
return __builtin_cpu_supports ("avx512bw") &&
--
2.43.0
