diff --git a/tools/build_wheels.sh b/tools/build_wheels.sh
index 0b9e49dceb..6a4cdfa07a 100755
--- a/tools/build_wheels.sh
+++ b/tools/build_wheels.sh
@@ -40,7 +40,7 @@ then
     exit 1
 fi
 
-grep -v '^#' global-requirements.txt | while read req
+grep -v '^$\|#' global-requirements.txt | while read req
 do
     echo "Building $req"
     for v in $versions