Companion: wasm-builder support stable Rust (#6967)

* Companion: wasm-builder support stable Rust

* update lockfile for {"substrate"}

---------

Co-authored-by: parity-processbot <>

polkadot/parachain/test-parachains/halt/Cargo.toml

@@ -10,6 +10,7 @@ edition.workspace = true
 
 [build-dependencies]
 substrate-wasm-builder = { git = "https://github.com/paritytech/substrate", branch = "master" }
+rustversion = "1.0.6"
 
 [features]
 default = [ "std" ]

polkadot/parachain/test-parachains/halt/build.rs

@@ -17,5 +17,17 @@
 use substrate_wasm_builder::WasmBuilder;
 
 fn main() {
-	WasmBuilder::new().with_current_project().export_heap_base().build()
+	WasmBuilder::new().with_current_project().export_heap_base().build();
+
+	enable_alloc_error_handler();
 }
+
+#[rustversion::before(1.68)]
+fn enable_alloc_error_handler() {
+	if !cfg!(feature = "std") {
+		println!("cargo:rustc-cfg=enable_alloc_error_handler");
+	}
+}
+
+#[rustversion::since(1.68)]
+fn enable_alloc_error_handler() {}

polkadot/parachain/test-parachains/halt/src/lib.rs

@@ -17,10 +17,7 @@
 //! Basic parachain that executes forever.
 
 #![no_std]
-#![cfg_attr(
-	not(feature = "std"),
-	feature(core_intrinsics, lang_items, core_panic_info, alloc_error_handler)
-)]
+#![cfg_attr(enable_alloc_error_handler, feature(alloc_error_handler))]
 
 // Make the WASM binary available.
 #[cfg(feature = "std")]
@@ -39,10 +36,10 @@ pub fn wasm_binary_unwrap() -> &'static [u8] {
 #[panic_handler]
 #[no_mangle]
 pub fn panic(_info: &core::panic::PanicInfo) -> ! {
-	core::intrinsics::abort()
+	core::arch::wasm32::unreachable();
 }
 
-#[cfg(not(feature = "std"))]
+#[cfg(enable_alloc_error_handler)]
 #[alloc_error_handler]
 #[no_mangle]
 pub fn oom(_: core::alloc::Layout) -> ! {