diff --git a/artiq/firmware/libboard/build.rs b/artiq/firmware/libboard/build.rs
index 4bb8665df..a7b0335e5 100644
--- a/artiq/firmware/libboard/build.rs
+++ b/artiq/firmware/libboard/build.rs
@@ -12,6 +12,4 @@ fn main() {
     for line in f.lines() {
         println!("cargo:rustc-cfg={}", line.unwrap());
     }
-
-    println!("cargo:rustc-cfg={}", "board");
 }