gcc: init module (#7614)

modules/programs/gcc.nix

@@ -0,0 +1,36 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+let
+  cfg = config.programs.gcc;
+
+in
+{
+
+  meta.maintainers = [ lib.maintainers.bmrips ];
+
+  options.programs.gcc = {
+    enable = lib.mkEnableOption "{command}`gcc`.";
+    package = lib.mkPackageOption pkgs "gcc" { nullable = true; };
+    colors = lib.mkOption {
+      type = with lib.types; attrsOf str;
+      default = { };
+      description = "Settings for {env}`GCC_COLORS`";
+      example = {
+        error = "01;31";
+      };
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    home.packages = lib.mkIf (cfg.package != null) [ cfg.package ];
+    home.sessionVariables.GCC_COLORS = lib.mkIf (cfg.colors != { }) (
+      lib.concatStringsSep ":" (lib.mapAttrsToList (n: v: "${n}=${v}") cfg.colors)
+    );
+  };
+
+}