Horton

Compile error on the aarch64 platform: Missing asm/hwcap.h

高增琦 <pgf00a@gmail.com>

View thread
From: 高增琦 <pgf00a@gmail.com>
To: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2025-11-14T04:02:30Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Fix pg_popcount_aarch64.c to build with ancient glibc releases.

  2. Fix pg_crc32c_armv8_choose.c to build with ancient glibc releases.

Hi,

Compile error on CentOS Linux release 7.6.1810 (AltArch) with the message
“‘HWCAP_CRC32’ undeclared”.

Relevant code from discussion:
https://www.postgresql.org/message-id/4496616.iHFcN1HehY%40portable-bastien
It mentions: "It doesn't look like I need to include <asm/hwcap.h> from
Bastien's
original message, because <sys/auxv.h> pulls in <bits/hwcap.h>
already."

However, the bits/hwcap.h file included with glibc in CentOS 7.6 lacks
these symbol definitions (the file is nearly empty). This file appears to
be an internal glibc dependency, so it's preferable to directly use
asm/hwcap.h for the required symbol definitions.

After modifying the code to add `include <asm/hwcap.h>`, the compilation
succeeded.

-- 
GaoZengqi
pgf00a@gmail.com
zengqigao@gmail.com