Ticket #43224: 43224.patch

src/wp-includes/formatting.php

@@ -1094 +1094 @@
 }
 
 /**
+ * Checks support for utf8 in the installed PCRE library.
+ *
+ * @since 5.0.0
+ *
+ * @staticvar bool $can
+ *
+ * @return bool True if installed PCRE library supports the `/u` flag.
+ */
+function wp_can_utf8_pcre() {
+        static $can = null;
+
+        if ( ! isset( $can ) ) {
+                $can = (bool) @preg_match( '/^./u', 'a' );
+        }
+
+        return $can;
+}
+
+/**
  * Checks for invalid UTF8 in a string.
  *
  * @since 2.8.0
@@ -1121 +1140 @@
                 return $string;
         }
 
-        // Check for support for utf8 in the installed PCRE library once and store the result in a static
-        static $utf8_pcre = null;
-        if ( ! isset( $utf8_pcre ) ) {
-                $utf8_pcre = @preg_match( '/^./u', 'a' );
-        }
         // We can't demand utf8 in the PCRE installation, so just return the string in those cases
-        if ( ! $utf8_pcre ) {
+        if ( ! wp_can_utf8_pcre() ) {
                 return $string;
         }