From 27fa9d33e1355ae1ef1c0a072f9b511858dfef85 Mon Sep 17 00:00:00 2001
From: Matt Caswell <matt@openssl.org>
Date: Wed, 23 Oct 2024 14:57:20 +0100
Subject: [PATCH] Fix builds on riscv64 using musl

Some environments using musl are reported to have the hwprobe.h include
file but not have the __NR_riscv_hwprobe define.

Fixes #25772

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
Reviewed-by: Paul Dale <ppzgs1@gmail.com>
Reviewed-by: Todd Short <todd.short@me.com>
(Merged from https://github.com/openssl/openssl/pull/25787)
---
 include/crypto/riscv_arch.h | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/include/crypto/riscv_arch.h b/include/crypto/riscv_arch.h
index 4b3573f5a34..885842763d9 100644
--- a/include/crypto/riscv_arch.h
+++ b/include/crypto/riscv_arch.h
@@ -15,7 +15,14 @@
 
 # if defined(OPENSSL_SYS_LINUX) && !defined(FIPS_MODULE)
 #  if __has_include(<asm/hwprobe.h>)
-#   define OSSL_RISCV_HWPROBE
+#   include <sys/syscall.h>
+#   /*
+     * Some environments using musl are reported to have the hwprobe.h include
+     * file but not have the __NR_riscv_hwprobe define.
+     */
+#   ifdef __NR_riscv_hwprobe
+#    define OSSL_RISCV_HWPROBE
+#   endif
 #  endif
 # endif
 
-- 
2.47.2