bootstrap: Only add rustc_randomized_layouts if the crate has it

Author: GuillaumeGomez

library/Cargo.lock

@@ -235,6 +235,7 @@ name = "proc_macro"
 version = "0.0.0"
 dependencies = [
  "core",
+ "rustc-literal-escaper",
  "std",
 ]
 
@@ -310,6 +311,10 @@ dependencies = [
  "rustc-std-workspace-core",
 ]
 
+[[package]]
+name = "rustc-literal-escaper"
+version = "0.0.1"
+
 [[package]]
 name = "rustc-std-workspace-alloc"
 version = "1.99.0"

library/proc_macro/Cargo.toml

@@ -9,4 +9,4 @@ std = { path = "../std" }
 # `core` when resolving doc links. Without this line a different `core` will be
 # loaded from sysroot causing duplicate lang items and other similar errors.
 core = { path = "../core" }
-rustc-literal-escaper = "0.0.1"
+rustc-literal-escaper = { version = "0.0.2", features = ["rustc-dep-of-std"] }

library/proc_macro/src/lib.rs

@@ -27,6 +27,7 @@
 #![feature(panic_can_unwind)]
 #![feature(restricted_std)]
 #![feature(rustc_attrs)]
+#![feature(stmt_expr_attributes)]
 #![feature(extend_one)]
 #![recursion_limit = "256"]
 #![allow(internal_features)]

src/bootstrap/src/lib.rs

@@ -748,7 +748,7 @@ impl Build {
             features.push("llvm");
         }
         // keep in sync with `bootstrap/compile.rs:rustc_cargo_env`
-        if self.config.rust_randomize_layout {
+        if self.config.rust_randomize_layout && check("rustc_randomized_layouts") {
             features.push("rustc_randomized_layouts");
         }