diff --git a/gcc/ada/ChangeLog b/gcc/ada/ChangeLog
index 6f08ad2efff..bea321400f3 100644
--- a/gcc/ada/ChangeLog
+++ b/gcc/ada/ChangeLog
@@ -1,3 +1,8 @@
+2018-05-28  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* repinfo.adb (Compute_Max_Length): Skip _Parent component.
+	(List_Record_Layout): Likewise.
+
 2018-05-28  Ed Schonberg  <schonberg@adacore.com>
 
 	* sem_util.adb (Is_Function_Result): Add a warning if a postcondition
diff --git a/gcc/ada/repinfo.adb b/gcc/ada/repinfo.adb
index 07c034bf77c..38b2334b3de 100644
--- a/gcc/ada/repinfo.adb
+++ b/gcc/ada/repinfo.adb
@@ -915,6 +915,12 @@ package body Repinfo is
                goto Continue;
             end if;
 
+            --  Skip _Parent component in extension (to avoid overlap)
+
+            if Chars (Comp) = Name_uParent then
+               goto Continue;
+            end if;
+
             --  All other cases
 
             declare
@@ -1010,6 +1016,12 @@ package body Repinfo is
                goto Continue;
             end if;
 
+            --  Skip _Parent component in extension (to avoid overlap)
+
+            if Chars (Comp) = Name_uParent then
+               goto Continue;
+            end if;
+
             --  All other cases
 
             declare