diff --git a/src/wp-includes/functions.php b/src/wp-includes/functions.php
index a4cfa13cd20dc..dd0066cf3fb63 100644
--- a/src/wp-includes/functions.php
+++ b/src/wp-includes/functions.php
@@ -594,10 +594,10 @@ function get_weekstartend( $mysqlstring, $start_of_week = '' ) {
 	$day = mktime( 0, 0, 0, $md, $mm, $my );
 
 	// The day of the week from the timestamp.
-	$weekday = gmdate( 'w', $day );
+	$weekday = (int) gmdate( 'w', $day );
 
 	if ( ! is_numeric( $start_of_week ) ) {
-		$start_of_week = get_option( 'start_of_week' );
+		$start_of_week = (int) get_option( 'start_of_week' );
 	}
 
 	if ( $weekday < $start_of_week ) {
@@ -609,6 +609,7 @@ function get_weekstartend( $mysqlstring, $start_of_week = '' ) {
 
 	// $start + 1 week - 1 second.
 	$end = $start + WEEK_IN_SECONDS - 1;
+
 	return compact( 'start', 'end' );
 }
 
diff --git a/src/wp-includes/general-template.php b/src/wp-includes/general-template.php
index 1d9fc98b843f7..e96f0f7c37429 100644
--- a/src/wp-includes/general-template.php
+++ b/src/wp-includes/general-template.php
@@ -2373,7 +2373,7 @@ function get_calendar( $initial = true, $display = true ) {
 	}
 
 	// See how much we should pad in the beginning.
-	$pad = calendar_week_mod( gmdate( 'w', $unixmonth ) - $week_begins );
+	$pad = calendar_week_mod( (int) gmdate( 'w', $unixmonth ) - $week_begins );
 	if ( 0 != $pad ) {
 		$calendar_output .= "\n\t\t" . '<td colspan="' . esc_attr( $pad ) . '" class="pad">&nbsp;</td>';
 	}
@@ -2412,12 +2412,12 @@ function get_calendar( $initial = true, $display = true ) {
 
 		$calendar_output .= '</td>';
 
-		if ( 6 == calendar_week_mod( gmdate( 'w', mktime( 0, 0, 0, $thismonth, $day, $thisyear ) ) - $week_begins ) ) {
+		if ( 6 == calendar_week_mod( (int) gmdate( 'w', mktime( 0, 0, 0, $thismonth, $day, $thisyear ) ) - $week_begins ) ) {
 			$newrow = true;
 		}
 	}
 
-	$pad = 7 - calendar_week_mod( gmdate( 'w', mktime( 0, 0, 0, $thismonth, $day, $thisyear ) ) - $week_begins );
+	$pad = 7 - calendar_week_mod( (int) gmdate( 'w', mktime( 0, 0, 0, $thismonth, $day, $thisyear ) ) - $week_begins );
 	if ( 0 != $pad && 7 != $pad ) {
 		$calendar_output .= "\n\t\t" . '<td class="pad" colspan="' . esc_attr( $pad ) . '">&nbsp;</td>';
 	}