ada: gnatbind: subprogram spec no longer exists

If a subprogram spec S is present while compiling something that
says "with S;", but the spec is absent while compiling the body
of S, then gnatbind fails to detect the mismatch.  The spec and
body of S might have different parameter and result types.
This patch fixes gnatbind to detect this case and give an error.

gcc/ada/

	* bcheck.adb (Check_Consistency_Of_Sdep): Split out new procedure.
	Add check for special case of subprogram spec that no longer
	exists.
	(Check_Consistency): Call Check_Consistency_Of_Sdep, except when
	Reified_Child_Spec is True. No need for "goto Continue" or "exit
	Sdep_Loop".
	* ali.ads (Subunit_Name, Unit_Name): Change the type to
	Unit_Name_Type. Add a comment pointing to the ALI file
	documentation, because it's in a somewhat-surprising place.
	* ali.adb (Scan_ALI): Subunit_Name and Unit_Name are now
	Unit_Name_Type. Remove comment explaining why Name_Find is used;
	Name_Find is the usual case. Do not remove the "%s" or "%b" from
	the Unit_Name. We need to be able to distinguish specs and bodies.
	This is also necessary to obey the invariant of Unit_Name_Type.
	* binde.adb (Write_Closure): Subunit_Name is now Unit_Name_Type.
	* clean.adb (Clean_Executables): Likewise.

1 files changed, 3 insertions, 6 deletions

diff --git a/gcc/ada/ali.adb b/gcc/ada/ali.adb
index 6bf48c0..69a91bc 100644
--- a/gcc/ada/ali.adb
+++ b/gcc/ada/ali.adb
@@ -3287,8 +3287,8 @@ package body ALI is
 
             --  Acquire (sub)unit and reference file name entries
 
-            Sdep.Table (Sdep.Last).Subunit_Name := No_Name;
-            Sdep.Table (Sdep.Last).Unit_Name    := No_Name;
+            Sdep.Table (Sdep.Last).Subunit_Name := No_Unit_Name;
+            Sdep.Table (Sdep.Last).Unit_Name    := No_Unit_Name;
             Sdep.Table (Sdep.Last).Rfile        :=
               Sdep.Table (Sdep.Last).Sfile;
             Sdep.Table (Sdep.Last).Start_Line   := 1;
@@ -3304,16 +3304,13 @@ package body ALI is
                      Add_Char_To_Name_Buffer (Getc);
                   end loop;
 
-                  --  Set the (sub)unit name. Note that we use Name_Find rather
-                  --  than Name_Enter here as the subunit name may already
-                  --  have been put in the name table by the Project Manager.
+                  --  Set the (sub)unit name.
 
                   if Name_Len <= 2
                     or else Name_Buffer (Name_Len - 1) /= '%'
                   then
                      Sdep.Table (Sdep.Last).Subunit_Name := Name_Find;
                   else
-                     Name_Len := Name_Len - 2;
                      Sdep.Table (Sdep.Last).Unit_Name := Name_Find;
                   end if;