Update Rust

default.nix

@@ -32,7 +32,6 @@ let
     llvmPackages_12.bintools
     rustc-nightly
     cargo-nightly
-    xargo
     wasmtime
     rust-bindgen
     rustfmt
@@ -173,7 +172,6 @@ rec {
       buildInputs = rtsBuildInputs;
 
       preBuild = ''
-        export XARGO_HOME=$PWD/xargo-home
         export CARGO_HOME=$PWD/cargo-home
 
         # this replicates logic from nixpkgs’ pkgs/build-support/rust/default.nix
@@ -441,7 +439,6 @@ rec {
 
   filecheck = nixpkgs.linkFarm "FileCheck"
     [ { name = "bin/FileCheck"; path = "${nixpkgs.llvm}/bin/FileCheck";} ];
-  inherit (nixpkgs) xargo;
 
   # gitMinimal is used by nix/gitSource.nix; building it here warms the nix cache
   inherit (nixpkgs) gitMinimal;

nix/default.nix

@@ -51,7 +51,7 @@ let
         # Rust nightly
         (self: super: let
           moz_overlay = import self.sources.nixpkgs-mozilla self super;
-          rust-channel = moz_overlay.rustChannelOf { date = "2020-07-22"; channel = "nightly"; };
+          rust-channel = moz_overlay.rustChannelOf { date = "2021-08-29"; channel = "nightly"; };
         in rec {
           rustc-nightly = rust-channel.rust.override {
             targets = [
@@ -67,7 +67,6 @@ let
             rustc = rustc-nightly;
             cargo = cargo-nightly;
           };
-          xargo = self.callPackage ./xargo.nix {};
         })
 
         # wasm-profiler

rts/Makefile

@@ -210,11 +210,11 @@ $(TOMMATH_BINDINGS_RS): | _build
 
 
 $(RTS_RUST_WASM_A): $(TOMMATH_BINDINGS_RS) $(RTS_RUST_FILES) $(RTS_CARGO_FILES) | _build/wasm
-	cd motoko-rts && xargo build --release --target=wasm32-unknown-emscripten
+	cd motoko-rts && cargo build --release --target=wasm32-unknown-emscripten -Zbuild-std=core,alloc
 	cp motoko-rts/target/wasm32-unknown-emscripten/release/libmotoko_rts.a $@
 
 $(RTS_RUST_DEBUG_WASM_A): $(TOMMATH_BINDINGS_RS) $(RTS_RUST_FILES) $(RTS_CARGO_FILES) | _build/wasm
-	cd motoko-rts && xargo build --target=wasm32-unknown-emscripten
+	cd motoko-rts && cargo build --target=wasm32-unknown-emscripten -Zbuild-std=core,alloc
 	cp motoko-rts/target/wasm32-unknown-emscripten/debug/libmotoko_rts.a $@
 
 #
@@ -268,5 +268,4 @@ clean:
 	  mo-rts-debug.wasm \
 	  motoko-rts/target \
 	  motoko-rts-tests/target \
-	  motoko-rts/xargo-home \
 	  motoko-rts/cargo-home

rts/README.md

@@ -58,13 +58,10 @@ See `motoko-rts/src/bigint.rs` for the technical details.
 Rust build
 ----------
 
-The Rust parts are built from `motoko-rts`, using `xargo` and `cargo`.
+The Rust parts are built from `motoko-rts`, using `cargo`.
 
-To build this in nix, we need pre-fetch some dependencies (currently
-`compiler_builtins` and `libc`). This works in `nix-build` by:
-
- * Adding`compiler_builtins` as a dependency in `Cargo.toml` (even though not
-   needed), so that it shows up with a hash in `Cargo.lock`
+To build this in nix, we need pre-fetch some dependencies (currently `libc`).
+This works in `nix-build` by:
 
  * Building a directory with vendored sources in `default.nix` (see `rustDeps`)
 

rts/motoko-rts-tests/src/main.rs

@@ -1,4 +1,4 @@
-#![feature(ptr_offset_from, map_first_last, clamp)]
+#![feature(map_first_last)]
 
 mod bigint;
 mod bitmap;

rts/motoko-rts/Cargo.toml

@@ -23,20 +23,6 @@ libc = { version = "0.2.81", default_features = false }
 motoko-rts-macros = { path = "../motoko-rts-macros" }
 static_assertions = "1.1.0"
 
-# Added here so that it ends up in Cargo.lock, so that nix will pre-fetch it
-[dependencies.compiler_builtins]
-version = "0.1.39"
-# Without this feature we get dozens of duplicate symbol errors when generating
-# the final shared .wasm file:
-#
-#     wasm-ld: error: duplicate symbol: __multi3
-#     >>> defined in _build/wasm/libmotoko_rts.a(compiler_builtins-d709bd899857aa61.compiler_builtins.3abndchk-cgu.0.rcgu.o)
-#     >>> defined in _build/wasm/libmotoko_rts.a(compiler_builtins-06d1ead628e1f468.compiler_builtins.6moz1ltd-cgu.0.rcgu.o)
-#
-# It seems like we're linking multiple versions of compiler_builtins in the same
-# shared library, which we should fix at some point. TODO
-features = ["mangled-names"]
-
 [profile.dev]
 panic = "abort"
 

rts/motoko-rts/native/Cargo.toml

@@ -13,10 +13,6 @@ libc = { version = "0.2.73", default_features = false }
 motoko-rts-macros = { path = "../../motoko-rts-macros" }
 static_assertions = "1.1.0"
 
-[dependencies.compiler_builtins]
-version = "0.1.39"
-features = ["mangled-names"]
-
 [profile.dev]
 panic = "abort"
 

rts/motoko-rts/src/lib.rs

@@ -2,13 +2,7 @@
 
 #![no_std]
 // TODO (osa): Some of these are stabilized, we need to update rustc
-#![feature(
-    arbitrary_self_types,
-    assoc_char_funcs,
-    core_intrinsics,
-    panic_info_message,
-    ptr_offset_from
-)]
+#![feature(arbitrary_self_types, core_intrinsics, panic_info_message)]
 
 #[macro_use]
 mod print;