buildroot/package/boost/0002-src-event-cpp-fix-build-on-riscv32.patch

From d2061419501bdd6761e9380ed5b91233f6c4e67e Mon Sep 17 00:00:00 2001
From: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Date: Fri, 21 May 2021 21:30:04 +0200
Subject: [PATCH] src/event.cpp: fix build on riscv32

riscv32 fails to build because __NR_futex is not defined on this
architecture:

libs/log/src/event.cpp: In member function 'void boost::log::v2_mt_posix::aux::futex_based_event::wait()':
libs/log/src/event.cpp:38:29: error: '__NR_futex' was not declared in this scope
   38 | #define BOOST_LOG_SYS_FUTEX __NR_futex
      |                             ^~~~~~~~~~

Fixes:
 - http://autobuild.buildroot.org/results/8c8135fd7c0517c66c9b3975c494da6d7934cc1b

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
[Retrieved from:
https://github.com/boostorg/log/commit/d2061419501bdd6761e9380ed5b91233f6c4e67e]
---
 src/event.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/libs/log/src/event.cpp b/libs/log/src/event.cpp
index 5485154d7..f576648c6 100644
--- a/libs/log/src/event.cpp
+++ b/libs/log/src/event.cpp
@@ -34,8 +34,13 @@
 // Some Android NDKs (Google NDK and older Crystax.NET NDK versions) don't define SYS_futex
 #if defined(SYS_futex)
 #define BOOST_LOG_SYS_FUTEX SYS_futex
-#else
+#elif defined(__NR_futex)
 #define BOOST_LOG_SYS_FUTEX __NR_futex
+// riscv32 defines a different system call instead of __NR_futex
+#elif defined(__NR_futex_time64)
+#define BOOST_LOG_SYS_FUTEX __NR_futex_time64
+#else
+#error "Unable to find a suitable futex"
 #endif
 
 #if defined(FUTEX_WAIT_PRIVATE)