From 901ed9b352b41f034e17bc540725082a488fce31 Mon Sep 17 00:00:00 2001
From: John Naylor <john.naylor@postgresql.org>
Date: Fri, 8 May 2026 16:44:25 +0700
Subject: [PATCH] Fix universal builds on MacOS

Commit 16743db06 assumed that the CPUID instruction was always
available when the usual x86 symbols were defined. That is not the
case, so zero out the info rather than error out.

Reported-by: Jakob Egger <jakob@eggerapps.at>
Reported-by: Tobias Bussmann <t.bussmann@gmx.net>
Suggested-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/223EA201-A0E8-4A13-B220-EB903E8DF817@eggerapps.at
---
 src/port/pg_cpu_x86.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/port/pg_cpu_x86.c b/src/port/pg_cpu_x86.c
index f22167da9af..f61f0940431 100644
--- a/src/port/pg_cpu_x86.c
+++ b/src/port/pg_cpu_x86.c
@@ -63,12 +63,11 @@ mask_available(uint32 value, uint32 mask)
 static inline void
 pg_cpuid(int leaf, unsigned int *reg)
 {
+	memset(reg, 0, 4 * sizeof(unsigned int));
 #if defined(HAVE__GET_CPUID)
 	__get_cpuid(leaf, &reg[EAX], &reg[EBX], &reg[ECX], &reg[EDX]);
 #elif defined(HAVE__CPUID)
 	__cpuid((int *) reg, leaf);
-#else
-#error cpuid instruction not available
 #endif
 }