diff --git a/build.sh b/build.sh
index 82a63352..ed4e7af2 100755
--- a/build.sh
+++ b/build.sh
@@ -16,6 +16,7 @@ elif [[ "$OSTYPE" == "darwin"* ]]; then
   RESULT=$PHYS_DIR/$TARGET_FILE
   PIPY_DIR=$(dirname $RESULT)
   OS_NAME=macos
+  export SDKROOT=$(xcrun --show-sdk-path)
 fi
 
 # Number of processors to build.