diff --git a/src/tools/rust-analyzer/crates/project-model/src/toolchain_info/rustc_cfg.rs b/src/tools/rust-analyzer/crates/project-model/src/toolchain_info/rustc_cfg.rs
index afcc8120794..4bf9b59e7d0 100644
--- a/src/tools/rust-analyzer/crates/project-model/src/toolchain_info/rustc_cfg.rs
+++ b/src/tools/rust-analyzer/crates/project-model/src/toolchain_info/rustc_cfg.rs
@@ -66,7 +66,7 @@ fn rustc_print_cfg(
         QueryConfig::Cargo(sysroot, cargo_toml) => {
             let mut cmd = sysroot.tool(Tool::Cargo, cargo_toml.parent());
             cmd.envs(extra_env);
-            cmd.args(["rustc"]).args(RUSTC_ARGS);
+            cmd.args(["rustc", "-Z", "unstable-options"]).args(RUSTC_ARGS);
             if let Some(target) = target {
                 cmd.args(["--target", target]);
             }