Merge pull request #82963 from zouyee/unbound

fix docker_build_opts bound variable

build/lib/release.sh

@@ -345,6 +345,15 @@ function kube::release::create_docker_images_for_server() {
       return 1
     fi
 
+    # provide `--pull` argument to `docker build` if `KUBE_BUILD_PULL_LATEST_IMAGES`
+    # is set to y or Y; otherwise try to build the image without forcefully
+    # pulling the latest base image.
+    local DOCKER_BUILD_OPTS=()
+    if [[ "${KUBE_BUILD_PULL_LATEST_IMAGES}" =~ [yY] ]]; then
+        DOCKER_BUILD_OPTS+=("--pull")
+    fi
+    local -r docker_build_opts="${DOCKER_BUILD_OPTS[@]}"
+
     for wrappable in "${binaries[@]}"; do
 
       local oldifs=$IFS
@@ -375,14 +384,7 @@ EOF
           echo "COPY nsswitch.conf /etc/" >> "${docker_file_path}"
         fi
 
-        # provide `--pull` argument to `docker build` if `KUBE_BUILD_PULL_LATEST_IMAGES`
-        # is set to y or Y; otherwise try to build the image without forcefully
-        # pulling the latest base image.
-        local -a docker_build_opts=()
-        if [[ "${KUBE_BUILD_PULL_LATEST_IMAGES}" =~ [yY] ]]; then
-            docker_build_opts+=("--pull")
-        fi
-        "${DOCKER[@]}" build "${docker_build_opts[@]}" -q -t "${docker_image_tag}" "${docker_build_path}" >/dev/null
+        "${DOCKER[@]}" build ${docker_build_opts} -q -t "${docker_image_tag}" "${docker_build_path}" >/dev/null
         # If we are building an official/alpha/beta release we want to keep
         # docker images and tag them appropriately.
         local -r release_docker_image_tag="${KUBE_DOCKER_REGISTRY-$docker_registry}/${binary_name}-${arch}:${KUBE_DOCKER_IMAGE_TAG-$docker_tag}"