[gcc r13-7449] ada: Fix internal error on loop iterator filter with -gnatVa

[gcc r13-7449] ada: Fix internal error on loop iterator filter with -gnatVa

[Eric Botcazou]

https://gcc.gnu.org/g:3b66becf77e7ae6a36a2e97ec386ff21c9f2b5ff

commit r13-7449-g3b66becf77e7ae6a36a2e97ec386ff21c9f2b5ff
Author: Eric Botcazou <ebotcazou@adacore.com>
Date:   Wed May 17 17:05:14 2023 +0200

    ada: Fix internal error on loop iterator filter with -gnatVa
    
    The problem is that the condition of the iterator filter is expanded early,
    before it is integrated into an if statement of the loop body, so there is
    no place to attach the actions generated by this expansion.
    
    This happens only for simple loops, i.e. with a parameter specification, so
    the fix uses the same approach for them as for loops based on iterators.
    
    gcc/ada/
    
            * sinfo.ads (Iterator_Filter): Document field.
            * sem_ch5.adb (Analyze_Iterator_Specification): Move comment around.
            (Analyze_Loop_Parameter_Specification): Only preanalyze the iterator
            filter, if any.
            * exp_ch5.adb (Expand_N_Loop_Statement): Analyze the new list built
            when an iterator filter is present.

Diff:
---
 gcc/ada/exp_ch5.adb |  1 +
 gcc/ada/sem_ch5.adb | 11 +++++++----
 gcc/ada/sinfo.ads   |  5 +++++
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/gcc/ada/exp_ch5.adb b/gcc/ada/exp_ch5.adb
index 265e1a74b93..d605f75d147 100644
--- a/gcc/ada/exp_ch5.adb
+++ b/gcc/ada/exp_ch5.adb
@@ -5610,6 +5610,7 @@ package body Exp_Ch5 is
                   New_List (Make_If_Statement (Loc,
                     Condition => Iterator_Filter (LPS),
                     Then_Statements => Stats)));
+               Analyze_List (Statements (N));
             end if;
 
             --  Deal with loop over predicates
diff --git a/gcc/ada/sem_ch5.adb b/gcc/ada/sem_ch5.adb
index ab5a2083a00..6b8f9e43183 100644
--- a/gcc/ada/sem_ch5.adb
+++ b/gcc/ada/sem_ch5.adb
@@ -2853,10 +2853,10 @@ package body Sem_Ch5 is
          end if;
       end if;
 
-      if Present (Iterator_Filter (N)) then
-         --  Preanalyze the filter. Expansion will take place when enclosing
-         --  loop is expanded.
+      --  Preanalyze the filter. Expansion will take place when enclosing
+      --  loop is expanded.
 
+      if Present (Iterator_Filter (N)) then
          Preanalyze_And_Resolve (Iterator_Filter (N), Standard_Boolean);
       end if;
    end Analyze_Iterator_Specification;
@@ -3570,8 +3570,11 @@ package body Sem_Ch5 is
          end;
       end if;
 
+      --  Preanalyze the filter. Expansion will take place when enclosing
+      --  loop is expanded.
+
       if Present (Iterator_Filter (N)) then
-         Analyze_And_Resolve (Iterator_Filter (N), Standard_Boolean);
+         Preanalyze_And_Resolve (Iterator_Filter (N), Standard_Boolean);
       end if;
 
       --  A loop parameter cannot be effectively volatile (SPARK RM 7.1.3(4)).
diff --git a/gcc/ada/sinfo.ads b/gcc/ada/sinfo.ads
index c25db08bc96..79fef3e0046 100644
--- a/gcc/ada/sinfo.ads
+++ b/gcc/ada/sinfo.ads
@@ -1899,6 +1899,11 @@ package Sinfo is
    --    Present in variable reference markers. Set when the original variable
    --    reference constitutes a write of the variable.
 
+   --  Iterator_Filter
+   --    Present in N_Loop_Parameter_Specification and N_Iterator_Specification
+   --    nodes for Ada 2022. It is used to store the condition present in the
+   --    eponymous Ada 2022 construct.
+
    --  Itype
    --    Used in N_Itype_Reference node to reference an itype for which it is
    --    important to ensure that it is defined. See description of this node