diff --git a/scripts/release.sh b/scripts/release.sh
index f6361f3..e3dd583 100755
--- a/scripts/release.sh
+++ b/scripts/release.sh
@@ -14,11 +14,11 @@ usage() { printf "usage: %s <tag>\n" "${BASH_SOURCE[0]##*/}"; exit 0; }
 
 bail() { printf "error: %s\n" "$1" "${@:2}"; exit 1; }
 
-[ -z "$1" ] && usage
-[[ "$1" != v* ]] && bail "tag name should start with 'v'"
+tag=$1
+[ -z "$tag" ] && usage
+[[ "$tag" != v* ]] && bail "tag name should start with 'v'"
 
 changelog=$(git diff -U0 "$changelog_file" | grep '^[+][^+]' | sed 's/^[+]//;s/^###\s*//')
-[ -z "$changelog" ] && bail "$changelog_file is not updated"
 
 sed "s/^version = \".*\" $version_suffix$/version = \"${1#v}\" $version_suffix/g" \
     -i -- */Cargo.toml
@@ -28,11 +28,11 @@ gawk -i inplace \
     '/\.TH\s.*+"8".*"System Administration"/{ $4 = date } 1' man*/*
 
 git add -A
-git commit -m "$commit_prefix$1"
+git commit -m "$commit_prefix$tag"
 git show
 
 git -c user.name="$tagger_name" \
     -c user.email="$tagger_email" \
     -c user.signingkey="$signing_key" \
-    tag -s -a "$1" -m "$tag_prefix$1" -m "$changelog"
-git tag -v "$1"
+    tag -s -a "$tag" -m "$tag_prefix$tag" -m "$changelog"
+git tag -v "$tag"