diff --git a/Cargo.toml b/Cargo.toml
index 2e34717f419f..02098b135f75 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -37,7 +37,8 @@ smallvec = "1.6.1"
 #gimli = { path = "../" }
 
 [features]
-default = ["jit", "inline_asm"]
+# Enable features not ready to be enabled when compiling as part of rustc
+unstable-features = ["jit", "inline_asm"]
 jit = ["cranelift-jit", "libloading"]
 inline_asm = []
 
diff --git a/build_system/build_backend.rs b/build_system/build_backend.rs
index 1df2bcc4541c..150b6d01a6b3 100644
--- a/build_system/build_backend.rs
+++ b/build_system/build_backend.rs
@@ -4,7 +4,7 @@ use std::process::Command;
 
 pub(crate) fn build_backend(channel: &str, host_triple: &str) -> PathBuf {
     let mut cmd = Command::new("cargo");
-    cmd.arg("build").arg("--target").arg(host_triple);
+    cmd.arg("build").arg("--target").arg(host_triple).arg("--features").arg("unstable-features");
 
     match channel {
         "debug" => {}