add a FIXME

Signed-off-by: onur-ozkan <work@onurozkan.dev>

Author: onur-ozkan

src/bootstrap/src/core/builder/cargo.rs

@@ -112,8 +112,7 @@ impl Cargo {
         let mut cargo = builder.cargo(compiler, mode, source_type, target, cmd_kind);
 
         match cmd_kind {
-            // No need to configure the target linker for these command types,
-            // as they don't invoke rustc at all.
+            // No need to configure the target linker for these command types.
             Kind::Clean | Kind::Check | Kind::Suggest | Kind::Format | Kind::Setup => {}
             _ => {
                 cargo.configure_linker(builder);
@@ -205,6 +204,8 @@ impl Cargo {
         self
     }
 
+    // FIXME(onur-ozkan): Add coverage to make sure modifications to this function
+    // doesn't cause cache invalidations (e.g., #130108).
     fn configure_linker(&mut self, builder: &Builder<'_>) -> &mut Cargo {
         let target = self.target;
         let compiler = self.compiler;