[gcc r12-2054] [Ada] Spurious conformance error on expression function

[gcc r12-2054] [Ada] Spurious conformance error on expression function

[Pierre-Marie de Rodat]

https://gcc.gnu.org/g:daf9bc6aeab822da203c01beb47d2c9e11ab3635

commit r12-2054-gdaf9bc6aeab822da203c01beb47d2c9e11ab3635
Author: Ed Schonberg <schonberg@adacore.com>
Date:   Sat May 1 19:55:36 2021 -0400

    [Ada] Spurious conformance error on expression function
    
    gcc/ada/
    
            * sem_ch6.adb (Analyze_Subprogram_Body_Helper): Do not perform
            conformance check when the subprogram body has been created for
            an expression function that is not a completion of a previous
            specification, because the profile of the constructed body is
            copied from the expression function itself.

Diff:
---
 gcc/ada/sem_ch6.adb | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/gcc/ada/sem_ch6.adb b/gcc/ada/sem_ch6.adb
index 4b58d593733..c7d4b961d47 100644
--- a/gcc/ada/sem_ch6.adb
+++ b/gcc/ada/sem_ch6.adb
@@ -4585,6 +4585,17 @@ package body Sem_Ch6 is
             then
                Conformant := True;
 
+            --  Finally, a body generated for an expression function copies
+            --  the profile of the function and no check is needed either.
+            --  If the body is the completion of a previous function
+            --  declared elsewhere, the conformance check is required.
+
+            elsif Nkind (N) = N_Subprogram_Body
+              and then Was_Expression_Function (N)
+              and then Sloc (Spec_Id) = Sloc (Body_Id)
+            then
+               Conformant := True;
+
             else
                Check_Conformance
                  (Body_Id, Spec_Id,