uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

pkgs/development/compilers/rust/default.nix

@@ -0,0 +1,89 @@
+{ rustcVersion
+, rustcSha256
+, enableRustcDev ? true
+, bootstrapVersion
+, bootstrapHashes
+, selectRustPackage
+, rustcPatches ? []
+, llvmBootstrapForDarwin
+, llvmShared
+, llvmSharedForBuild
+, llvmSharedForHost
+, llvmSharedForTarget
+, llvmPackages # Exposed through rustc for LTO in Firefox
+}:
+{ stdenv, lib
+, buildPackages
+, newScope, callPackage
+, CoreFoundation, Security, SystemConfiguration
+, pkgsBuildTarget, pkgsBuildBuild
+, makeRustPlatform
+}:
+
+let
+  # Use `import` to make sure no packages sneak in here.
+  lib' = import ../../../build-support/rust/lib { inherit lib; };
+in
+{
+  lib = lib';
+
+  # Backwards compat before `lib` was factored out.
+  inherit (lib') toTargetArch toTargetOs toRustTarget toRustTargetSpec;
+
+  # This just contains tools for now. But it would conceivably contain
+  # libraries too, say if we picked some default/recommended versions from
+  # `cratesIO` to build by Hydra and/or try to prefer/bias in Cargo.lock for
+  # all vendored Carnix-generated nix.
+  #
+  # In the end game, rustc, the rust standard library (`core`, `std`, etc.),
+  # and cargo would themselves be built with `buildRustCreate` like
+  # everything else. Tools and `build.rs` and procedural macro dependencies
+  # would be taken from `buildRustPackages` (and `bootstrapRustPackages` for
+  # anything provided prebuilt or their build-time dependencies to break
+  # cycles / purify builds). In this way, nixpkgs would be in control of all
+  # bootstrapping.
+  packages = {
+    prebuilt = callPackage ./bootstrap.nix {
+      version = bootstrapVersion;
+      hashes = bootstrapHashes;
+    };
+    stable = lib.makeScope newScope (self: let
+      # Like `buildRustPackages`, but may also contain prebuilt binaries to
+      # break cycle. Just like `bootstrapTools` for nixpkgs as a whole,
+      # nothing in the final package set should refer to this.
+      bootstrapRustPackages = self.buildRustPackages.overrideScope' (_: _:
+        lib.optionalAttrs (stdenv.buildPlatform == stdenv.hostPlatform)
+          (selectRustPackage buildPackages).packages.prebuilt);
+      bootRustPlatform = makeRustPlatform bootstrapRustPackages;
+    in {
+      # Packages suitable for build-time, e.g. `build.rs`-type stuff.
+      buildRustPackages = (selectRustPackage buildPackages).packages.stable;
+      # Analogous to stdenv
+      rustPlatform = makeRustPlatform self.buildRustPackages;
+      rustc = self.callPackage ./rustc.nix ({
+        version = rustcVersion;
+        sha256 = rustcSha256;
+        inherit enableRustcDev;
+        inherit llvmShared llvmSharedForBuild llvmSharedForHost llvmSharedForTarget llvmPackages;
+
+        patches = rustcPatches;
+
+        # Use boot package set to break cycle
+        rustPlatform = bootRustPlatform;
+      } // lib.optionalAttrs (stdenv.cc.isClang && stdenv.hostPlatform == stdenv.buildPlatform) {
+        stdenv = llvmBootstrapForDarwin.stdenv;
+        pkgsBuildBuild = pkgsBuildBuild // { targetPackages.stdenv = llvmBootstrapForDarwin.stdenv; };
+        pkgsBuildHost = pkgsBuildBuild // { targetPackages.stdenv = llvmBootstrapForDarwin.stdenv; };
+        pkgsBuildTarget = pkgsBuildTarget // { targetPackages.stdenv = llvmBootstrapForDarwin.stdenv; };
+      });
+      rustfmt = self.callPackage ./rustfmt.nix { inherit Security; };
+      cargo = self.callPackage ./cargo.nix {
+        # Use boot package set to break cycle
+        rustPlatform = bootRustPlatform;
+        inherit CoreFoundation Security;
+      };
+      clippy = self.callPackage ./clippy.nix { inherit Security; };
+      rls = self.callPackage ./rls { inherit CoreFoundation Security SystemConfiguration; };
+    });
+  };
+}