make bootstrap disable lld on stable

Author: lqd

src/bootstrap/src/core/build_steps/compile.rs

@@ -1360,7 +1360,7 @@ pub fn rustc_cargo_env(builder: &Builder<'_>, cargo: &mut Cargo, target: TargetS
     }
 
     // Enable rustc's env var for `rust-lld` when requested.
-    if builder.config.lld_enabled {
+    if builder.config.lld_enabled && builder.config.channel != "stable" {
         cargo.env("CFG_USE_SELF_CONTAINED_LINKER", "1");
     }
 

src/bootstrap/src/core/config/toml/rust.rs

@@ -657,6 +657,7 @@ impl Config {
         //   when the config sets `rust.lld = false`
         if default_lld_opt_in_targets().contains(&self.host_target.triple.to_string())
             && self.hosts == [self.host_target]
+            && self.channel != "stable"
         {
             let no_llvm_config = self
                 .target_config