diff --git a/pkgs/build-support/rust/sysroot/src.nix b/pkgs/build-support/rust/sysroot/src.nix
index 3d11b62dd315..664702e82c31 100644
--- a/pkgs/build-support/rust/sysroot/src.nix
+++ b/pkgs/build-support/rust/sysroot/src.nix
@@ -19,7 +19,7 @@ stdenv.mkDerivation {
   + ''
     ${buildPackages.python3.withPackages (ps: with ps; [ toml ])}/bin/python3 ${./cargo.py}
     mkdir -p $out/src
-    touch $out/src/lib.rs
+    echo '#![no_std]' > $out/src/lib.rs
     cp Cargo.toml $out/Cargo.toml
     cp ${./Cargo.lock} $out/Cargo.lock
   '';