[Ada] Check missing function returns in generic template

[Arnaud Charlet <charlet at adacore dot com>]

This patch fixes the problem of not catching a missing return in
a generic function (the error was caught at instantiation time, but
it is an illegality in the template).

with apa; use apa;
procedure mainmr is
   function fool2 is new fool;
begin
   null;
end;

package apa is
   generic
   function fool return integer;
end apa;

package body apa is
   function fool return integer is
   begin
      null;
   end fool;
end apa;

If we compile mainmr.adb, we now get the message on the template:

Compiling: mainmr.adb

     1. with apa; use apa;
     2. procedure mainmr is
     3.    function fool2 is new fool;
     4. begin
     5.    null;
     6. end;

==============Error messages for source file: apa.adb
     2.    function fool return integer is
           |
        >>> missing "return" statement in function body

 6 lines: 1 error

Prior to this patch, the error was issued on the instantiation,
and not issued at all if the generic was never instantiated.

Tested on x86_64-pc-linux-gnu, committed on trunk

2010-06-23  Robert Dewar  <dewar@adacore.com>

	* sem_ch6.adb (Analyze_Subprogram_Body_Helper): Properly handle
	checking returns in generic case.
	(Check_Missing_Return): New procedure.

Attachment: difs
Description: Text document