[gcc r14-1851] ada: Accept aspect Always_Terminates on packages

[gcc r14-1851] ada: Accept aspect Always_Terminates on packages

[Marc Poulhi?s]

https://gcc.gnu.org/g:3ec78e11471c898328053884ac328cb898f91144

commit r14-1851-g3ec78e11471c898328053884ac328cb898f91144
Author: Piotr Trojanek <trojanek@adacore.com>
Date:   Fri May 12 14:06:07 2023 +0200

    ada: Accept aspect Always_Terminates on packages
    
    The recently added aspect Always_Terminates is now allowed on packages
    and generic packages, but only when it has no arguments. The intuitive
    meaning is that all subprograms declared in such a package are always
    terminating.
    
    gcc/ada/
    
            * contracts.adb (Add_Contract_Item): Add pragma Always_Terminates to
            package contract.
            * sem_prag.adb (Analyze_Pragma): Accept pragma Always_Terminates on
            packages and generic packages, but only when it has no arguments.

Diff:
---
 gcc/ada/contracts.adb |  3 +++
 gcc/ada/sem_prag.adb  | 20 ++++++++++++++++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/gcc/ada/contracts.adb b/gcc/ada/contracts.adb
index 0e87cee3ef5..26bc4b39735 100644
--- a/gcc/ada/contracts.adb
+++ b/gcc/ada/contracts.adb
@@ -296,6 +296,9 @@ package body Contracts is
          elsif Prag_Nam = Name_Part_Of and then Is_Generic_Instance (Id) then
             Add_Classification;
 
+         elsif Prag_Nam = Name_Always_Terminates then
+            Add_Contract_Test_Case;
+
          --  The pragma is not a proper contract item
 
          else
diff --git a/gcc/ada/sem_prag.adb b/gcc/ada/sem_prag.adb
index b1e4439b9f2..bcae43ff59d 100644
--- a/gcc/ada/sem_prag.adb
+++ b/gcc/ada/sem_prag.adb
@@ -13332,9 +13332,14 @@ package body Sem_Prag is
             Subp_Decl :=
               Find_Related_Declaration_Or_Body (N, Do_Checks => True);
 
-            --  Generic subprogram
+            --  Generic subprogram and package declaration
 
-            if Nkind (Subp_Decl) = N_Generic_Subprogram_Declaration then
+            if Nkind (Subp_Decl) in N_Generic_Declaration then
+               null;
+
+            --  Package declaration
+
+            elsif Nkind (Subp_Decl) = N_Package_Declaration then
                null;
 
             --  Body acts as spec
@@ -13394,6 +13399,17 @@ package body Sem_Prag is
                return;
             end if;
 
+            --  Pragma Always_Terminates applied to packages doesn't allow any
+            --  expression.
+
+            if Is_Package_Or_Generic_Package (Spec_Id)
+              and then Arg_Count /= 0
+            then
+               Error_Msg_N (Fix_Error
+                 ("pragma % applied to package cannot have arguments"), N);
+               return;
+            end if;
+
             --  A pragma that applies to a Ghost entity becomes Ghost for the
             --  purposes of legality checks and removal of ignored Ghost code.