diff --git a/build.rs b/build.rs
index 39388d3b..3844c11a 100644
--- a/build.rs
+++ b/build.rs
@@ -902,6 +902,7 @@ fn main_impl() -> Result<()> {
         "LIB",
         "LD_LIBRARY_PATH",
         "PYO3_PYTHON",
+        "PYO3_CROSS",
         "PYO3_CROSS_LIB_DIR",
         "PYO3_CROSS_PYTHON_VERSION",
     ] {