--- a/src/bootstrap/src/core/config/config.rs
+++ b/src/bootstrap/src/core/config/config.rs
@@ -628,7 +628,7 @@
             );
         }
 
-        let bootstrap_override_lld =
+        let mut bootstrap_override_lld =
             rust_bootstrap_override_lld.or(rust_bootstrap_override_lld_legacy).unwrap_or_default();
 
         if rust_optimize.as_ref().is_some_and(|v| matches!(v, RustOptimize::Bool(false))) {
@@ -978,6 +978,20 @@
         let is_host_system_llvm =
             is_system_llvm(&target_config, llvm_from_ci, host_target, host_target);
 
+        // Self-contained bootstrap LLD comes from the stage0 sysroot (`rust-lld`), whose LLVM
+        // version may differ from an externally configured host LLVM. In that case, linking LLVM
+        // bitcode objects can fail with "Unknown attribute kind".
+        if is_host_system_llvm
+            && matches!(bootstrap_override_lld, BootstrapOverrideLld::SelfContained)
+        {
+            eprintln!(
+                "WARNING: `rust.bootstrap-override-lld = \"self-contained\"` with external host \
+                 `llvm-config` can cause LLVM bitcode version mismatches; falling back to \
+                 `rust.bootstrap-override-lld = \"external\"` for bootstrap linking."
+            );
+            bootstrap_override_lld = BootstrapOverrideLld::External;
+        }
+
         if llvm_from_ci {
             let warn = |option: &str| {
                 println!(
@@ -1042,21 +1056,27 @@
             let default_linux_linker_override = match linker_override {
                 DefaultLinuxLinkerOverride::Off => continue,
                 DefaultLinuxLinkerOverride::SelfContainedLldCc => {
-                    // If we automatically default to the self-contained LLD linker,
-                    // we also need to handle the rust.lld option.
-                    match rust_lld_enabled {
-                        // If LLD was not enabled explicitly, we enable it, unless LLVM config has
-                        // been set
-                        None if !is_host_system_llvm => {
-                            lld_enabled = true;
-                            Some(DefaultLinuxLinkerOverride::SelfContainedLldCc)
+                    // If bootstrap is explicitly using an external `lld` binary, do not also
+                    // embed a self-contained rust-lld default into rustc's Linux target spec.
+                    if matches!(bootstrap_override_lld, BootstrapOverrideLld::External) {
+                        None
+                    } else {
+                        // If we automatically default to the self-contained LLD linker,
+                        // we also need to handle the rust.lld option.
+                        match rust_lld_enabled {
+                            // If LLD was not enabled explicitly, we enable it, unless LLVM config has
+                            // been set
+                            None if !is_host_system_llvm => {
+                                lld_enabled = true;
+                                Some(DefaultLinuxLinkerOverride::SelfContainedLldCc)
+                            }
+                            None => None,
+                            // If it was enabled already, we don't need to do anything
+                            Some(true) => Some(DefaultLinuxLinkerOverride::SelfContainedLldCc),
+                            // If it was explicitly disabled, we do not apply the
+                            // linker override
+                            Some(false) => None,
                         }
-                        None => None,
-                        // If it was enabled already, we don't need to do anything
-                        Some(true) => Some(DefaultLinuxLinkerOverride::SelfContainedLldCc),
-                        // If it was explicitly disabled, we do not apply the
-                        // linker override
-                        Some(false) => None,
                     }
                 }
             };