diff --git a/gcc/ada/ChangeLog b/gcc/ada/ChangeLog
index a5f3843ca00..8e5a19bc9e8 100644
--- a/gcc/ada/ChangeLog
+++ b/gcc/ada/ChangeLog
@@ -1,3 +1,8 @@
+2019-09-26  Alexandre Oliva <oliva@adacore.com>
+
+	* gcc-interface/decl.c (components_to_record): Set
+	DECL_SIZE_UNIT for zero-sized fields.
+
 2019-09-26  Arnaud Charlet  <charlet@adacore.com>
 
 	* osint.adb (OS_Time_To_GNAT_Time): Remove dependency on To_C/To_Ada
diff --git a/gcc/ada/gcc-interface/decl.c b/gcc/ada/gcc-interface/decl.c
index 67b938ee7ee..77c6c9f12e7 100644
--- a/gcc/ada/gcc-interface/decl.c
+++ b/gcc/ada/gcc-interface/decl.c
@@ -7928,6 +7928,7 @@ components_to_record (Node_Id gnat_component_list, Entity_Id gnat_record_type,
 
       if (DECL_SIZE (gnu_field) && integer_zerop (DECL_SIZE (gnu_field)))
 	{
+	  DECL_SIZE_UNIT (gnu_field) = size_zero_node;
 	  DECL_FIELD_OFFSET (gnu_field) = size_zero_node;
 	  SET_DECL_OFFSET_ALIGN (gnu_field, BIGGEST_ALIGNMENT);
 	  DECL_FIELD_BIT_OFFSET (gnu_field) = bitsize_zero_node;