From 7f979717f5275e54db2a9b44ce6ea29a4f18af97 Mon Sep 17 00:00:00 2001
From: Wanja Zaeske <wanja.zaeske@dlr.de>
Date: Mon, 18 Sep 2023 15:17:50 +0200
Subject: [PATCH] fix #1: allow injection of CMake flags

---
 flake.nix         | 5 +++++
 sel4-sys/build.rs | 5 +++++
 2 files changed, 10 insertions(+)

diff --git a/flake.nix b/flake.nix
index d3744d7..708b5d4 100644
--- a/flake.nix
+++ b/flake.nix
@@ -69,6 +69,9 @@
             cargo = rust-toolchains.stable;
             rustc = rust-toolchains.stable;
           });
+
+          SEL4_ADDITIONAL_CMAKE_FLAGS = "-DCROSS_COMPILER_PREFIX=arm-none-eabihf-";
+
         in
         rec {
 
@@ -186,6 +189,8 @@
                   pkgs.nixpkgs-fmt # formatting nix files
                   pkgs.nodePackages.prettier # prettifier for MarkDown and YAML
                 ];
+
+              inherit SEL4_ADDITIONAL_CMAKE_FLAGS;
             };
           };
 
diff --git a/sel4-sys/build.rs b/sel4-sys/build.rs
index 49e7bf1..213d211 100644
--- a/sel4-sys/build.rs
+++ b/sel4-sys/build.rs
@@ -147,6 +147,11 @@ fn cmake_config(config: SeL4Config, build_dir: impl AsRef<Path>) -> Result<()> {
 
     args.append(&mut config.get_cmake_args());
 
+    // allows user overrides to the build script
+    if let Ok(flags) = std::env::var("SEL4_ADDITIONAL_CMAKE_FLAGS") {
+        args.push(flags);
+    }
+
     let output = cmd("cmake", args).read()?;
 
     for line in output.lines() {