diff --git a/crates/mbe/Cargo.toml b/crates/mbe/Cargo.toml
index f50d796e13..2046fa943a 100644
--- a/crates/mbe/Cargo.toml
+++ b/crates/mbe/Cargo.toml
@@ -27,5 +27,8 @@ span.workspace = true
 [dev-dependencies]
 test-utils.workspace = true
 
+[features]
+in-rust-tree = ["parser/in-rust-tree", "syntax/in-rust-tree"]
+
 [lints]
-workspace = true
\ No newline at end of file
+workspace = true
diff --git a/crates/proc-macro-srv-cli/Cargo.toml b/crates/proc-macro-srv-cli/Cargo.toml
index 980eab2696..a559ba0175 100644
--- a/crates/proc-macro-srv-cli/Cargo.toml
+++ b/crates/proc-macro-srv-cli/Cargo.toml
@@ -14,10 +14,12 @@ proc-macro-api.workspace = true
 
 [features]
 sysroot-abi = ["proc-macro-srv/sysroot-abi"]
+in-rust-tree = ["proc-macro-srv/in-rust-tree", "sysroot-abi"]
+
 
 [[bin]]
 name = "rust-analyzer-proc-macro-srv"
 path = "src/main.rs"
 
 [lints]
-workspace = true
\ No newline at end of file
+workspace = true
diff --git a/crates/proc-macro-srv-cli/src/main.rs b/crates/proc-macro-srv-cli/src/main.rs
index 000a526e9f..87f7555b02 100644
--- a/crates/proc-macro-srv-cli/src/main.rs
+++ b/crates/proc-macro-srv-cli/src/main.rs
@@ -1,5 +1,9 @@
 //! A standalone binary for `proc-macro-srv`.
 //! Driver for proc macro server
+#![cfg_attr(feature = "in-rust-tree", feature(rustc_private))]
+#[cfg(feature = "in-rust-tree")]
+extern crate rustc_driver as _;
+
 use std::io;
 
 fn main() -> std::io::Result<()> {
diff --git a/crates/proc-macro-srv/Cargo.toml b/crates/proc-macro-srv/Cargo.toml
index b6686fa5b6..9c4375559c 100644
--- a/crates/proc-macro-srv/Cargo.toml
+++ b/crates/proc-macro-srv/Cargo.toml
@@ -38,6 +38,7 @@ proc-macro-test.path = "./proc-macro-test"
 
 [features]
 sysroot-abi = ["proc-macro-test/sysroot-abi"]
+in-rust-tree = ["mbe/in-rust-tree", "sysroot-abi"]
 
 [lints]
-workspace = true
\ No newline at end of file
+workspace = true
diff --git a/crates/proc-macro-srv/src/lib.rs b/crates/proc-macro-srv/src/lib.rs
index 7cd6df2df8..f1575a5b0b 100644
--- a/crates/proc-macro-srv/src/lib.rs
+++ b/crates/proc-macro-srv/src/lib.rs
@@ -11,11 +11,12 @@
 //!   rustc rather than `unstable`. (Although in general ABI compatibility is still an issue)…
 
 #![cfg(any(feature = "sysroot-abi", rust_analyzer))]
-#![feature(proc_macro_internals, proc_macro_diagnostic, proc_macro_span)]
+#![feature(proc_macro_internals, proc_macro_diagnostic, proc_macro_span, rustc_private)]
 #![warn(rust_2018_idioms, unused_lifetimes)]
 #![allow(unreachable_pub, internal_features)]
 
 extern crate proc_macro;
+extern crate rustc_driver as _;
 
 mod dylib;
 mod server;
diff --git a/crates/rust-analyzer/src/bin/main.rs b/crates/rust-analyzer/src/bin/main.rs
index 6f40a4c88e..7432f0f7a7 100644
--- a/crates/rust-analyzer/src/bin/main.rs
+++ b/crates/rust-analyzer/src/bin/main.rs
@@ -5,8 +5,7 @@
 #![warn(rust_2018_idioms, unused_lifetimes)]
 #![cfg_attr(feature = "in-rust-tree", feature(rustc_private))]
 #[cfg(feature = "in-rust-tree")]
-#[allow(unused_extern_crates)]
-extern crate rustc_driver;
+extern crate rustc_driver as _;
 
 mod logger;
 mod rustc_wrapper;