diff --git a/src/bootstrap/src/core/build_steps/compile.rs b/src/bootstrap/src/core/build_steps/compile.rs
index 3c0d074807d39..73f29d6bb6f45 100644
--- a/src/bootstrap/src/core/build_steps/compile.rs
+++ b/src/bootstrap/src/core/build_steps/compile.rs
@@ -239,7 +239,7 @@ impl Step for Std {
         let mut cargo = if self.is_for_mir_opt_tests {
             let mut cargo = builder.cargo(compiler, Mode::Std, SourceType::InTree, target, "check");
             cargo.rustflag("-Zalways-encode-mir");
-            std_cargo(builder, target, compiler.stage, &mut cargo);
+            cargo.arg("--manifest-path").arg(builder.src.join("library/sysroot/Cargo.toml"));
             cargo
         } else {
             let mut cargo = builder.cargo(compiler, Mode::Std, SourceType::InTree, target, "build");