From 761af68257feeae4b6253530ee1e1349da35c253 Mon Sep 17 00:00:00 2001
From: Mukesh Panchal <mukeshpanchal27@users.noreply.github.com>
Date: Thu, 17 Sep 2026 15:57:19 +0530
Subject: [PATCH 1/3] Hoist loop-invariant calls out of get_the_category_rss()

---
 src/wp-includes/feed.php | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/wp-includes/feed.php b/src/wp-includes/feed.php
index 453cc9063cf75..734d5fa0f70f8 100644
--- a/src/wp-includes/feed.php
+++ b/src/wp-includes/feed.php
@@ -406,13 +406,24 @@ function get_the_category_rss( $type = null ) {
 
 	$cat_names = array_unique( $cat_names );
 
+	$blog_charset = '';
+	$atom_scheme  = '';
+	if ( ! empty( $cat_names ) ) {
+		if ( 'atom' === $type ) {
+			// Escaped here as the scheme is the same for every term in the loop below.
+			$atom_scheme = esc_attr( get_bloginfo_rss( 'url' ) );
+		} elseif ( 'rdf' !== $type ) {
+			$blog_charset = get_option( 'blog_charset' );
+		}
+	}
+
 	foreach ( $cat_names as $cat_name ) {
 		if ( 'rdf' === $type ) {
 			$the_list .= "\t\t<dc:subject><![CDATA[$cat_name]]></dc:subject>\n";
 		} elseif ( 'atom' === $type ) {
-			$the_list .= sprintf( '<category scheme="%1$s" term="%2$s" />', esc_attr( get_bloginfo_rss( 'url' ) ), esc_attr( $cat_name ) );
+			$the_list .= sprintf( '<category scheme="%1$s" term="%2$s" />', $atom_scheme, esc_attr( $cat_name ) );
 		} else {
-			$the_list .= "\t\t<category><![CDATA[" . html_entity_decode( $cat_name, ENT_COMPAT, get_option( 'blog_charset' ) ) . "]]></category>\n";
+			$the_list .= "\t\t<category><![CDATA[" . html_entity_decode( $cat_name, ENT_COMPAT, $blog_charset ) . "]]></category>\n";
 		}
 	}
 

From a6f3c77996717e7a102bbe7183fbccfe2ee522ae Mon Sep 17 00:00:00 2001
From: Mukesh Panchal <mukeshpanchal27@users.noreply.github.com>
Date: Fri, 18 Sep 2026 08:34:58 +0530
Subject: [PATCH 2/3] Fix atom scheme escaping in feed.php

---
 src/wp-includes/feed.php | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/wp-includes/feed.php b/src/wp-includes/feed.php
index 734d5fa0f70f8..e13d05bb95c85 100644
--- a/src/wp-includes/feed.php
+++ b/src/wp-includes/feed.php
@@ -410,8 +410,7 @@ function get_the_category_rss( $type = null ) {
 	$atom_scheme  = '';
 	if ( ! empty( $cat_names ) ) {
 		if ( 'atom' === $type ) {
-			// Escaped here as the scheme is the same for every term in the loop below.
-			$atom_scheme = esc_attr( get_bloginfo_rss( 'url' ) );
+			$atom_scheme = get_bloginfo_rss( 'url' );
 		} elseif ( 'rdf' !== $type ) {
 			$blog_charset = get_option( 'blog_charset' );
 		}
@@ -421,7 +420,7 @@ function get_the_category_rss( $type = null ) {
 		if ( 'rdf' === $type ) {
 			$the_list .= "\t\t<dc:subject><![CDATA[$cat_name]]></dc:subject>\n";
 		} elseif ( 'atom' === $type ) {
-			$the_list .= sprintf( '<category scheme="%1$s" term="%2$s" />', $atom_scheme, esc_attr( $cat_name ) );
+			$the_list .= sprintf( '<category scheme="%1$s" term="%2$s" />', esc_attr( $atom_scheme ), esc_attr( $cat_name ) );
 		} else {
 			$the_list .= "\t\t<category><![CDATA[" . html_entity_decode( $cat_name, ENT_COMPAT, $blog_charset ) . "]]></category>\n";
 		}

From 71e4260bb3d3b1fc0b6cda6ec32ee51ccbb5f653 Mon Sep 17 00:00:00 2001
From: Mukesh Panchal <mukeshpanchal27@users.noreply.github.com>
Date: Fri, 18 Sep 2026 09:01:19 +0530
Subject: [PATCH 3/3] Avoid using empty()

Co-authored-by: Weston Ruter <westonruter@gmail.com>
---
 src/wp-includes/feed.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/wp-includes/feed.php b/src/wp-includes/feed.php
index e13d05bb95c85..b256ab3bcc348 100644
--- a/src/wp-includes/feed.php
+++ b/src/wp-includes/feed.php
@@ -408,7 +408,7 @@ function get_the_category_rss( $type = null ) {
 
 	$blog_charset = '';
 	$atom_scheme  = '';
-	if ( ! empty( $cat_names ) ) {
+	if ( $cat_names ) {
 		if ( 'atom' === $type ) {
 			$atom_scheme = get_bloginfo_rss( 'url' );
 		} elseif ( 'rdf' !== $type ) {