From e7c968fbf2edd32bb1d009207f873017e4bf5287 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vladim=C3=ADr=20=C4=8Cun=C3=A1t?= <vcunat@gmail.com>
Date: Fri, 3 Feb 2017 12:37:40 +0100
Subject: [PATCH] linuxPackages*.perf: fix build with default gcc

Broken since 9842a107.
---
 pkgs/os-specific/linux/kernel/perf.nix | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/pkgs/os-specific/linux/kernel/perf.nix b/pkgs/os-specific/linux/kernel/perf.nix
index 76f2662f21b..0bfd8dfe700 100644
--- a/pkgs/os-specific/linux/kernel/perf.nix
+++ b/pkgs/os-specific/linux/kernel/perf.nix
@@ -32,8 +32,11 @@ stdenv.mkDerivation {
   # bad `ld' and other stuff.
   NIX_CFLAGS_COMPILE = [
     "-Wno-error=cpp" "-Wno-error=bool-compare" "-Wno-error=deprecated-declarations"
-    "-Wno-error=unused-const-variable" "-Wno-error=misleading-indentation"
-  ];
+  ]
+    # gcc before 6 doesn't know these options
+    ++ stdenv.lib.optionals (hasPrefix "gcc-6" stdenv.cc.cc) [
+      "-Wno-error=unused-const-variable" "-Wno-error=misleading-indentation"
+    ];
 
   installFlags = "install install-man ASCIIDOC8=1";