buildRustPackage: factor out setting up .cargo/config to cargoSetupHook

This makes it possible to reuse this functionality as a hook in derivations that do not use buildRustPackage.
2021-02-10 07:01:24 +01:00
parent fd96ee6e9d
commit d083f412fa
4 changed files with 139 additions and 84 deletions
@@ -0,0 +1,49 @@
+{ buildPackages
+, callPackage
+, diffutils
+, lib
+, makeSetupHook
+, rust
+, stdenv
+, target ? rust.toRustTargetSpec stdenv.hostPlatform
+}:
+
+let
+  targetIsJSON = lib.hasSuffix ".json" target;
+
+  # see https://github.com/rust-lang/cargo/blob/964a16a28e234a3d397b2a7031d4ab4a428b1391/src/cargo/core/compiler/compile_kind.rs#L151-L168
+  # the "${}" is needed to transform the path into a /nix/store path before baseNameOf
+  shortTarget = if targetIsJSON then
+      (lib.removeSuffix ".json" (builtins.baseNameOf "${target}"))
+    else target;
+  ccForBuild="${buildPackages.stdenv.cc}/bin/${buildPackages.stdenv.cc.targetPrefix}cc";
+  ccForHost="${stdenv.cc}/bin/${stdenv.cc.targetPrefix}cc";
+in {
+  cargoSetupHook = callPackage ({ }:
+    makeSetupHook {
+      name = "cargo-setup-hook.sh";
+      deps = [ ];
+      substitutions = {
+        defaultConfig = ../fetchcargo-default-config.toml;
+
+        # Specify the stdenv's `diff` by abspath to ensure that the user's build
+        # inputs do not cause us to find the wrong `diff`.
+        # The `.nativeDrv` stanza works like nativeBuildInputs and ensures cross-compiling has the right version available.
+        diff = "${diffutils.nativeDrv or diffutils}/bin/diff";
+
+        # Target platform
+        rustTarget = ''
+          [target."${rust.toRustTarget stdenv.buildPlatform}"]
+          "linker" = "${ccForBuild}"
+          ${lib.optionalString (stdenv.buildPlatform.config != stdenv.hostPlatform.config) ''
+            [target."${shortTarget}"]
+            "linker" = "${ccForHost}"
+            ${# https://github.com/rust-lang/rust/issues/46651#issuecomment-433611633
+            lib.optionalString (stdenv.hostPlatform.isMusl && stdenv.hostPlatform.isAarch64) ''
+              "rustflags" = [ "-C", "target-feature=+crt-static", "-C", "link-arg=-lgcc" ]
+            ''}
+          ''}
+        '';
+      };
+    } ./cargo-setup-hook.sh) {};
+}