diff --git a/dist/index.js b/dist/index.js
index 0487a14..0cb4190 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -6809,7 +6809,7 @@ function generateComment({
 			file.link,
 			file.base && file.base.size ? c$1(dist(file.base.size)) : '—',
 			file.head && file.head.size ? (
-				(file.base.size ? sup(formatSize(file.diff.size)) : '') + c$1(dist(file.head.size))
+				(file.base && file.base.size ? sup(formatSize(file.diff.size)) : '') + c$1(dist(file.head.size))
 			) : '—',
 		]),
 		[
@@ -6844,7 +6844,7 @@ function generateComment({
 				file.link,
 				file.base && file.base.size ? c$1(dist(file.base.size)) : '—',
 				file.head && file.head.size ? (
-					(file.base.size ? sup(formatSize(file.diff.size)) : '') + c$1(dist(file.head.size))
+					(file.base && file.base.size ? sup(formatSize(file.diff.size)) : '') + c$1(dist(file.head.size))
 				) : '—',
 			]),
 		], {
diff --git a/src/templates/index.js b/src/templates/index.js
index 06ec680..28677a9 100644
--- a/src/templates/index.js
+++ b/src/templates/index.js
@@ -33,7 +33,7 @@ function generateComment({
 			file.link,
 			file.base && file.base.size ? c(byteSize(file.base.size)) : '—',
 			file.head && file.head.size ? (
-				(file.base.size ? sup(formatSize(file.diff.size)) : '') + c(byteSize(file.head.size))
+				(file.base && file.base.size ? sup(formatSize(file.diff.size)) : '') + c(byteSize(file.head.size))
 			) : '—',
 		]),
 		[
@@ -68,7 +68,7 @@ function generateComment({
 				file.link,
 				file.base && file.base.size ? c(byteSize(file.base.size)) : '—',
 				file.head && file.head.size ? (
-					(file.base.size ? sup(formatSize(file.diff.size)) : '') + c(byteSize(file.head.size))
+					(file.base && file.base.size ? sup(formatSize(file.diff.size)) : '') + c(byteSize(file.head.size))
 				) : '—',
 			]),
 		], {