From 3832b75e4e37be74c0311b4f03191c6e221966f0 Mon Sep 17 00:00:00 2001
From: Francesco Gazzetta <fgaz@fgaz.me>
Date: Mon, 20 Nov 2023 17:41:08 +0100
Subject: [PATCH] cmake: fix risc-v build failure

riscv64 is failing due to missing atomic ops in gcc 12.
This commit works around the problem by linking against libatomic.

It can be reverted when we switch to gcc 13 (#268097)
---
 pkgs/by-name/cm/cmake/package.nix | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pkgs/by-name/cm/cmake/package.nix b/pkgs/by-name/cm/cmake/package.nix
index a57314791501..1b8aefd1b911 100644
--- a/pkgs/by-name/cm/cmake/package.nix
+++ b/pkgs/by-name/cm/cmake/package.nix
@@ -138,6 +138,8 @@ stdenv.mkDerivation (finalAttrs: {
     "CFLAGS=-D_FILE_OFFSET_BITS=64"
     "CXXFLAGS=-D_FILE_OFFSET_BITS=64"
   ]
+  # Workaround missing atomic ops with gcc <13
+  ++ lib.optional stdenv.hostPlatform.isRiscV "LDFLAGS=-latomic"
   ++ [
     "--"
     # We should set the proper `CMAKE_SYSTEM_NAME`.