From defd393d9a989a21b5ca6faef5147437504f9967 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Mon, 5 Dec 2022 20:00:29 +0000
Subject: [PATCH] Remove rust toolchain channel check (#848)

* Remove assert_channel check

* Add RUSTC_BOOTSTRAP for building on stable
---
 crates/build/src/lib.rs      |  7 ++++++-
 crates/build/src/util/mod.rs | 29 -----------------------------
 2 files changed, 6 insertions(+), 30 deletions(-)

diff --git a/crates/build/src/lib.rs b/crates/build/src/lib.rs
index f71314903..893952f92 100644
--- a/crates/build/src/lib.rs
+++ b/crates/build/src/lib.rs
@@ -256,10 +256,15 @@ fn exec_cargo_for_wasm_target(
         } else {
             args.push("-Zbuild-std-features=panic_immediate_abort");
         }
-        let env = vec![(
+        let mut env = vec![(
             "RUSTFLAGS",
             Some("-C link-arg=-zstack-size=65536 -C link-arg=--import-memory -Clinker-plugin-lto -C target-cpu=mvp"),
         )];
+        if rustc_version::version_meta()?.channel == rustc_version::Channel::Stable {
+            // Allow nightly features on a stable toolchain
+            env.push(("RUSTC_BOOTSTRAP", Some("1")))
+        }
+
         util::invoke_cargo(command, &args, manifest_path.directory(), verbosity, env)?;
 
         Ok(())
diff --git a/crates/build/src/util/mod.rs b/crates/build/src/util/mod.rs
index 70fb3c987..43bfcc4cb 100644
--- a/crates/build/src/util/mod.rs
+++ b/crates/build/src/util/mod.rs
@@ -22,37 +22,12 @@ use anyhow::{
     Context,
     Result,
 };
-use rustc_version::Channel;
-use semver::Version;
 use std::{
     ffi::OsStr,
     path::Path,
     process::Command,
 };
 
-/// This makes sure we are building with a minimum `stable` toolchain version.
-fn assert_channel() -> Result<()> {
-    let meta = rustc_version::version_meta()?;
-    let min_version = Version::new(1, 63, 0);
-    match meta.channel {
-        Channel::Stable if meta.semver >= min_version => Ok(()),
-        Channel::Stable => {
-            anyhow::bail!(
-                "The minimum Rust version is {}. You are using {}.",
-                min_version,
-                meta.semver
-            )
-        }
-        _ => {
-            anyhow::bail!(
-                "Using the {:?} channel is not supported. \
-                Contracts should be built using a \"stable\" toolchain.",
-                format!("{:?}", meta.channel).to_lowercase(),
-            )
-        }
-    }
-}
-
 // Returns the current Rust toolchain formatted by `<channel>-<target-triple>`.
 pub(crate) fn rust_toolchain() -> Result<String> {
     let meta = rustc_version::version_meta()?;
@@ -85,7 +60,6 @@ where
     S: AsRef<OsStr>,
     P: AsRef<Path>,
 {
-    assert_channel()?;
     let cargo = std::env::var("CARGO").unwrap_or_else(|_| "cargo".to_string());
     let mut cmd = Command::new(cargo);
 
@@ -101,9 +75,6 @@ where
         cmd.current_dir(path);
     }
 
-    // Allow nightly features on a stable toolchain
-    cmd.env("RUSTC_BOOTSTRAP", "1");
-
     cmd.arg(command);
     cmd.args(args);
     match verbosity {