Only use substrate-wasm-builder when std feature is enabled. (#12790)

Co-authored-by: parity-processbot <>

substrate/client/executor/runtime-test/Cargo.toml

@@ -19,7 +19,7 @@ sp-runtime = { version = "7.0.0", default-features = false, path = "../../../pri
 sp-std = { version = "5.0.0", default-features = false, path = "../../../primitives/std" }
 
 [build-dependencies]
-substrate-wasm-builder = { version = "5.0.0-dev", path = "../../../utils/wasm-builder" }
+substrate-wasm-builder = { version = "5.0.0-dev", path = "../../../utils/wasm-builder", optional = true }
 
 [features]
 default = ["std"]
@@ -28,4 +28,5 @@ std = [
 	"sp-io/std",
 	"sp-runtime/std",
 	"sp-std/std",
+	"substrate-wasm-builder",
 ]

substrate/client/executor/runtime-test/build.rs

@@ -16,22 +16,26 @@
 // You should have received a copy of the GNU General Public License
 // along with this program. If not, see <https://www.gnu.org/licenses/>.
 
-use substrate_wasm_builder::WasmBuilder;
-
 fn main() {
 	// regular build
-	WasmBuilder::new()
-		.with_current_project()
-		.export_heap_base()
-		.import_memory()
-		.build();
+	#[cfg(feature = "std")]
+	{
+		substrate_wasm_builder::WasmBuilder::new()
+			.with_current_project()
+			.export_heap_base()
+			.import_memory()
+			.build();
+	}
 
 	// and building with tracing activated
-	WasmBuilder::new()
-		.with_current_project()
-		.export_heap_base()
-		.import_memory()
-		.set_file_name("wasm_binary_with_tracing.rs")
-		.append_to_rust_flags(r#"--cfg feature="with-tracing""#)
-		.build();
+	#[cfg(feature = "std")]
+	{
+		substrate_wasm_builder::WasmBuilder::new()
+			.with_current_project()
+			.export_heap_base()
+			.import_memory()
+			.set_file_name("wasm_binary_with_tracing.rs")
+			.append_to_rust_flags(r#"--cfg feature="with-tracing""#)
+			.build();
+	}
 }