diff --git a/cargo.sh b/cargo.sh
index 9b83deaf7ab..3e756696d9c 100755
--- a/cargo.sh
+++ b/cargo.sh
@@ -20,4 +20,4 @@ fi
 cmd=$1
 shift
 
-cargo +${TOOLCHAIN} $cmd --target $TARGET_TRIPLE $@
+RUSTDOCFLAGS=$RUSTFLAGS cargo +${TOOLCHAIN} $cmd --target $TARGET_TRIPLE $@