diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 6f8567c809e..e422d71bdfe 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2019-05-23  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gnat.dg/opt78.ad[sb]: New test.
+
 2019-05-23  Iain Sandoe  <iain@sandoe.co.uk>
 
 	PR rtl-optimisation/64895
diff --git a/gcc/testsuite/gnat.dg/opt78.adb b/gcc/testsuite/gnat.dg/opt78.adb
new file mode 100644
index 00000000000..e46c92b2759
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/opt78.adb
@@ -0,0 +1,16 @@
+-- { dg-do compile }
+-- { dg-options "-O" }
+
+package body Opt78 is
+
+   procedure Proc (P : UC; Msg : String) is
+      Default : UC := (1, "!");
+   begin
+      if P = Default then
+         raise Program_Error;
+      else
+         raise Constraint_Error;
+      end if;
+   end;
+
+end Opt78;
diff --git a/gcc/testsuite/gnat.dg/opt78.ads b/gcc/testsuite/gnat.dg/opt78.ads
new file mode 100644
index 00000000000..2c489bd7b38
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/opt78.ads
@@ -0,0 +1,13 @@
+package Opt78 is
+
+   subtype Reasonable is Integer range 1..10;
+
+   type UC (D: Reasonable := 2) is record
+      S: String (1 .. D) := "Hi";
+   end record;
+
+   type AUC is access all UC;
+
+   procedure Proc (P : UC; Msg : String);
+
+end Opt78;