[COMMITTED] ada: Fix deferred constant wrongly rejected

[COMMITTED] ada: Fix deferred constant wrongly rejected

[Marc Poulhiès]

From: Eric Botcazou <ebotcazou@adacore.com>

This recent regression occurs when the nominal subtype of the constant is a
discriminated record type with default discriminants.

gcc/ada/
	PR ada/110488
	* sem_ch3.adb (Analyze_Object_Declaration): Do not build a default
	subtype for a deferred constant in the definite case too.

Tested on x86_64-pc-linux-gnu, committed on master.

---
 gcc/ada/sem_ch3.adb | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/gcc/ada/sem_ch3.adb b/gcc/ada/sem_ch3.adb
index 92902a7debb..c79d323395f 100644
--- a/gcc/ada/sem_ch3.adb
+++ b/gcc/ada/sem_ch3.adb
@@ -5048,9 +5048,11 @@ package body Sem_Ch3 is
             Apply_Length_Check (E, T);
          end if;
 
-      --  When possible, build the default subtype
+      --  When possible, and not a deferred constant, build the default subtype
 
-      elsif Build_Default_Subtype_OK (T) then
+      elsif Build_Default_Subtype_OK (T)
+        and then (not Constant_Present (N) or else Present (E))
+      then
          if No (E) then
             Act_T := Build_Default_Subtype (T, N);
          else
-- 
2.42.0