From e3b9cba7cb47ec3e09d2e2801873cc834158520e Mon Sep 17 00:00:00 2001
From: Sergei Trofimovich <slyich@gmail.com>
Date: Sun, 5 Jun 2022 15:18:59 +0100
Subject: [PATCH] xboard: pull patch pending upstream inclusion for -fno-common
 toolchain support

Without the change build fails on upstream gcc-10 as:

    ld: evalgraph.o:(.bss+0x20): multiple definition of `ics_type'; backend.o:(.bss+0x1df910): first defined here
    ld: nevalgraph.o:(.bss+0x8): multiple definition of `currPvInfo'; backend.o:(.bss+0x1df908): first defined here
---
 pkgs/games/xboard/default.nix | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/pkgs/games/xboard/default.nix b/pkgs/games/xboard/default.nix
index 663207bd23c4..eefbb90114ff 100644
--- a/pkgs/games/xboard/default.nix
+++ b/pkgs/games/xboard/default.nix
@@ -1,6 +1,7 @@
 { lib
 , stdenv
 , fetchurl
+, fetchpatch
 , libX11
 , xorgproto
 , libXt
@@ -28,6 +29,16 @@ stdenv.mkDerivation rec {
     sha256 = "sha256-Ky5T6EKK2bbo3IpVs6UYM4GRGk2uLABy+pYpa7sZcNY=";
   };
 
+  patches = [
+    # Pull patch pending upstream inclusion for -fno-common toolchain support:
+    #   https://savannah.gnu.org/patch/index.php?10211
+    (fetchpatch {
+      name = "fno-common.patch";
+      url = "https://savannah.gnu.org/patch/download.php?file_id=53275";
+      sha256 = "sha256-ZOo9jAy1plFjhC5HXJQvXL+Zf7FL14asV3G4AwfgqTY=";
+    })
+  ];
+
   buildInputs = [
     libX11
     xorgproto