[gcc r12-1887] [Ada] More robust guard against cascaded errors with overlapping actuals

[Pierre-Marie de Rodat <pmderodat@gcc.gnu.org>]

https://gcc.gnu.org/g:3307a681fe6883008495d686f3b357dcbfb9537c

commit r12-1887-g3307a681fe6883008495d686f3b357dcbfb9537c
Author: Piotr Trojanek <trojanek@adacore.com>
Date:   Mon Apr 12 16:56:23 2021 +0200

    [Ada] More robust guard against cascaded errors with overlapping actuals
    
    gcc/ada/
    
            * sem_warn.adb (Warn_On_Overlapping_Actuals): Prevent cascaded
            errors once for the subprogram call, not for every pair of
            actual parameters.

Diff:
---
 gcc/ada/sem_warn.adb | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/gcc/ada/sem_warn.adb b/gcc/ada/sem_warn.adb
index 23f27711b5a..9e337f944de 100644
--- a/gcc/ada/sem_warn.adb
+++ b/gcc/ada/sem_warn.adb
@@ -3729,6 +3729,11 @@ package body Sem_Warn is
 
       if Nkind (N) not in N_Subprogram_Call | N_Entry_Call_Statement then
          return;
+
+      --  Guard against previous errors
+
+      elsif Error_Posted (N) then
+         return;
       end if;
 
       --  If a call C has two or more parameters of mode in out or out that are
@@ -3800,10 +3805,9 @@ package body Sem_Warn is
                   and then Is_Composite_Type (Etype (Form1)))
                then
 
-               --  Guard against previous errors
+                  --  Guard against previous errors
 
-                  if Error_Posted (N)
-                    or else No (Etype (Act1))
+                  if No (Etype (Act1))
                     or else No (Etype (Act2))
                   then
                      null;