ada: Treat Info-Warnings as Info messages

There was a general concept of info messages being a subset of
warnings. However that is no longer the case. Messages with an
info insertion character should be treated just as info messages.

gcc/ada/

	* atree.ads: Remove Warning_Info_Messages.
	* errout.adb: Remove various places where Warning_Info_Messages
	was used.
	* erroutc.adb: Remove various places where Warning_Info_Messages
	was used. Create Error_Msg_Object objects with only an info
	attribute if the message contained both info and warning insertion
	characters. New method Has_Switch_Tag for detecting if a message
	should have an error tag.
	* errutil.adb: Create Error_Msg_Object objects with only an info
	attribute if the message contained both info and warning insertion
	characters.

4 files changed, 96 insertions, 76 deletions

diff --git a/gcc/ada/atree.ads b/gcc/ada/atree.ads
index 2ecb386..834cc31 100644
--- a/gcc/ada/atree.ads
+++ b/gcc/ada/atree.ads
@@ -161,15 +161,11 @@ package Atree is
    --  Number of warnings detected. Initialized to zero at the start of
    --  compilation. This count includes the count of style and info messages.
 
-   Warning_Info_Messages : Nat := 0;
-   --  Number of info messages generated as warnings. Info messages are never
-   --  treated as errors (whether from use of the pragma, or the compiler
-   --  switch -gnatwe).
-
-   Report_Info_Messages : Nat := 0;
+   Info_Messages : Nat := 0;
    --  Number of info messages generated as reports. Info messages are never
    --  treated as errors (whether from use of the pragma, or the compiler
-   --  switch -gnatwe). Used under Spark_Mode to report proved checks.
+   --  switch -gnatwe). Used by GNATprove under SPARK_Mode to report proved
+   --  checks.
 
    Check_Messages : Nat := 0;
    --  Number of check messages generated. Check messages are neither warnings
diff --git a/gcc/ada/errout.adb b/gcc/ada/errout.adb
index 76c461a..1e6b0fe 100644
--- a/gcc/ada/errout.adb
+++ b/gcc/ada/errout.adb
@@ -283,10 +283,6 @@ package body Errout is
                M.Deleted := True;
                Warnings_Detected := Warnings_Detected - 1;
 
-               if M.Info then
-                  Warning_Info_Messages := Warning_Info_Messages - 1;
-               end if;
-
                if M.Warn_Err then
                   Warnings_Treated_As_Errors := Warnings_Treated_As_Errors - 1;
                end if;
@@ -428,7 +424,8 @@ package body Errout is
       --  that style checks are not considered warning messages for this
       --  purpose.
 
-      if Is_Warning_Msg and then Warnings_Suppressed (Orig_Loc) /= No_String
+      if Is_Warning_Msg
+        and then Warnings_Suppressed (Orig_Loc) /= No_String
       then
          return;
 
@@ -1049,6 +1046,33 @@ package body Errout is
          return;
       end if;
 
+      if Is_Info_Msg then
+
+         --  If the flag location is in the main extended source unit then for
+         --  sure we want the message since it definitely belongs.
+
+         if In_Extended_Main_Source_Unit (Sptr) then
+            null;
+
+         --  Keep info message if message text contains !!
+
+         elsif Has_Double_Exclam then
+            null;
+
+         --  Here is where we delete a message from a with'ed unit
+
+         else
+            Cur_Msg := No_Error_Msg;
+
+            if not Continuation then
+               Last_Killed := True;
+            end if;
+
+            return;
+         end if;
+
+      end if;
+
       --  Special check for warning message to see if it should be output
 
       if Is_Warning_Msg then
@@ -1064,7 +1088,7 @@ package body Errout is
          end if;
 
          --  If the flag location is in the main extended source unit then for
-         --  sure we want the warning since it definitely belongs
+         --  sure we want the warning since it definitely belongs.
 
          if In_Extended_Main_Source_Unit (Sptr) then
             null;
@@ -1210,6 +1234,11 @@ package body Errout is
          return;
       end if;
 
+      --  Warning, Style and Info attributes are mutually exclusive
+
+      pragma Assert (Boolean'Pos (Is_Warning_Msg) + Boolean'Pos (Is_Info_Msg) +
+        Boolean'Pos (Is_Style_Msg) <= 1);
+
       --  Here we build a new error object
 
       Errors.Append
@@ -1384,15 +1413,7 @@ package body Errout is
       --  Bump appropriate statistics counts
 
       if Errors.Table (Cur_Msg).Info then
-
-         --  Could be (usually is) both "info" and "warning"
-
-         if Errors.Table (Cur_Msg).Warn then
-            Warning_Info_Messages := Warning_Info_Messages + 1;
-            Warnings_Detected     := Warnings_Detected + 1;
-         else
-            Report_Info_Messages := Report_Info_Messages + 1;
-         end if;
+         Info_Messages := Info_Messages + 1;
 
       elsif Errors.Table (Cur_Msg).Warn
         or else Errors.Table (Cur_Msg).Style
@@ -1648,10 +1669,6 @@ package body Errout is
          if not Errors.Table (E).Deleted then
             Errors.Table (E).Deleted := True;
             Warnings_Detected := Warnings_Detected - 1;
-
-            if Errors.Table (E).Info then
-               Warning_Info_Messages := Warning_Info_Messages - 1;
-            end if;
          end if;
       end Delete_Warning;
 
@@ -1695,7 +1712,8 @@ package body Errout is
             Tag : constant String := Get_Warning_Tag (Cur);
 
          begin
-            if (CE.Warn and not CE.Deleted)
+            if CE.Warn
+              and then not CE.Deleted
               and then
                    (Warning_Specifically_Suppressed (CE.Sptr.Ptr, CE.Text, Tag)
                                                                 /= No_String
@@ -1968,7 +1986,6 @@ package body Errout is
 
       Warnings_Treated_As_Errors := 0;
       Warnings_Detected := 0;
-      Warning_Info_Messages := 0;
       Warnings_As_Errors_Count := 0;
 
       --  Initialize warnings tables
@@ -2640,8 +2657,7 @@ package body Errout is
          --  are also errors.
 
          declare
-            Warnings_Count : constant Int :=
-               Warnings_Detected - Warning_Info_Messages;
+            Warnings_Count : constant Int := Warnings_Detected;
 
             Compile_Time_Warnings : Int;
             --  Number of warnings that come from a Compile_Time_Warning
@@ -2702,12 +2718,12 @@ package body Errout is
             end if;
          end;
 
-         if Warning_Info_Messages + Report_Info_Messages /= 0 then
+         if Info_Messages /= 0 then
             Write_Str (", ");
-            Write_Int (Warning_Info_Messages + Report_Info_Messages);
+            Write_Int (Info_Messages);
             Write_Str (" info message");
 
-            if Warning_Info_Messages + Report_Info_Messages > 1 then
+            if Info_Messages > 1 then
                Write_Char ('s');
             end if;
          end if;
@@ -3419,23 +3435,19 @@ package body Errout is
          Write_Max_Errors;
       end if;
 
-      --  Even though Warning_Info_Messages are a subclass of warnings, they
-      --  must not be treated as errors when -gnatwe is in effect.
-
       if Warning_Mode = Treat_As_Error then
          declare
             Compile_Time_Pragma_Warnings : constant Nat :=
                Count_Compile_Time_Pragma_Warnings;
             Total : constant Int := Total_Errors_Detected + Warnings_Detected
-               - Warning_Info_Messages - Compile_Time_Pragma_Warnings;
+               - Compile_Time_Pragma_Warnings;
             --  We need to protect against a negative Total here, because
             --  if a pragma Compile_Time_Warning occurs in dead code, it
             --  gets counted in Compile_Time_Pragma_Warnings but not in
             --  Warnings_Detected.
          begin
             Total_Errors_Detected := Int'Max (Total, 0);
-            Warnings_Detected :=
-               Warning_Info_Messages + Compile_Time_Pragma_Warnings;
+            Warnings_Detected := Compile_Time_Pragma_Warnings;
          end;
       end if;
    end Output_Messages;
@@ -3630,10 +3642,6 @@ package body Errout is
                   Warnings_Detected := Warnings_Detected - 1;
                end if;
 
-               if Errors.Table (E).Info then
-                  Warning_Info_Messages := Warning_Info_Messages - 1;
-               end if;
-
                --  When warning about a runtime exception has been escalated
                --  into error, the starting message has increased the total
                --  errors counter, so here we decrease this counter.
diff --git a/gcc/ada/erroutc.adb b/gcc/ada/erroutc.adb
index f404018c..aa9aac4 100644
--- a/gcc/ada/erroutc.adb
+++ b/gcc/ada/erroutc.adb
@@ -59,6 +59,11 @@ package body Erroutc is
    --  from generic instantiations by using pragma Warnings around generic
    --  instances, as needed in GNATprove.
 
+   function Has_Switch_Tag (Id : Error_Msg_Id) return Boolean;
+   function Has_Switch_Tag (E_Msg : Error_Msg_Object) return Boolean;
+   --  Returns True if the E_Msg is Warning, Style or Info and has a non-empty
+   --  Warn_Char.
+
    ---------------
    -- Add_Class --
    ---------------
@@ -144,12 +149,7 @@ package body Erroutc is
 
             if Errors.Table (D).Info then
 
-               if Errors.Table (D).Warn then
-                  Warning_Info_Messages := Warning_Info_Messages - 1;
-                  Warnings_Detected := Warnings_Detected - 1;
-               else
-                  Report_Info_Messages := Report_Info_Messages - 1;
-               end if;
+               Info_Messages := Info_Messages - 1;
 
             elsif Errors.Table (D).Warn or else Errors.Table (D).Style then
                Warnings_Detected := Warnings_Detected - 1;
@@ -246,8 +246,7 @@ package body Erroutc is
    ------------------------
 
    function Compilation_Errors return Boolean is
-      Warnings_Count : constant Int
-         := Warnings_Detected - Warning_Info_Messages;
+      Warnings_Count : constant Int := Warnings_Detected;
    begin
       if Total_Errors_Detected /= 0 then
          return True;
@@ -330,6 +329,7 @@ package body Erroutc is
 
       w ("  Line               = ", Int (E.Line));
       w ("  Col                = ", Int (E.Col));
+      w ("  Info               = ", E.Info);
       w ("  Warn               = ", E.Warn);
       w ("  Warn_Err           = ", E.Warn_Err);
       w ("  Warn_Runtime_Raise = ", E.Warn_Runtime_Raise);
@@ -366,13 +366,11 @@ package body Erroutc is
    ------------------------
 
    function Get_Warning_Option (Id : Error_Msg_Id) return String is
-      Warn     : constant Boolean         := Errors.Table (Id).Warn;
       Style    : constant Boolean         := Errors.Table (Id).Style;
       Warn_Chr : constant String (1 .. 2) := Errors.Table (Id).Warn_Chr;
 
    begin
-      if (Warn or Style)
-        and then Warn_Chr /= "  "
+      if Has_Switch_Tag (Errors.Table (Id))
         and then Warn_Chr (1) /= '?'
       then
          if Warn_Chr = "$ " then
@@ -394,13 +392,11 @@ package body Erroutc is
    ---------------------
 
    function Get_Warning_Tag (Id : Error_Msg_Id) return String is
-      Warn     : constant Boolean         := Errors.Table (Id).Warn;
-      Style    : constant Boolean         := Errors.Table (Id).Style;
       Warn_Chr : constant String (1 .. 2) := Errors.Table (Id).Warn_Chr;
       Option   : constant String          := Get_Warning_Option (Id);
 
    begin
-      if Warn or Style then
+      if Has_Switch_Tag (Id) then
          if Warn_Chr = "? " then
             return "[enabled by default]";
          elsif Warn_Chr = "* " then
@@ -413,6 +409,23 @@ package body Erroutc is
       return "";
    end Get_Warning_Tag;
 
+   --------------------
+   -- Has_Switch_Tag --
+   --------------------
+
+   function Has_Switch_Tag (Id : Error_Msg_Id) return Boolean
+   is (Has_Switch_Tag (Errors.Table (Id)));
+
+   function Has_Switch_Tag (E_Msg : Error_Msg_Object) return Boolean
+   is
+      Warn     : constant Boolean         := E_Msg.Warn;
+      Style    : constant Boolean         := E_Msg.Style;
+      Info     : constant Boolean         := E_Msg.Info;
+      Warn_Chr : constant String (1 .. 2) := E_Msg.Warn_Chr;
+   begin
+      return (Warn or Style or Info) and then Warn_Chr /= "  ";
+   end Has_Switch_Tag;
+
    -------------
    -- Matches --
    -------------
@@ -918,6 +931,7 @@ package body Erroutc is
          Is_Unconditional_Msg := False;
          Is_Warning_Msg       := False;
          Is_Runtime_Raise     := False;
+         Warning_Msg_Char     := "  ";
 
          --  Check style message
 
@@ -962,7 +976,14 @@ package body Erroutc is
 
          elsif Msg (J) = '?' or else Msg (J) = '<' then
             if Msg (J) = '?' or else Error_Msg_Warn then
-               Is_Warning_Msg := not Is_Style_Msg;
+
+               --  Consider Info and Style messages as unique message types.
+               --  Those messages can have warning insertion characters within
+               --  them. However they should only be switch specific insertion
+               --  characters and not the generic ? or ?? warning insertion
+               --  characters.
+
+               Is_Warning_Msg := not (Is_Style_Msg or else Is_Info_Msg);
                J := J + 1;
                Warning_Msg_Char := Parse_Message_Class;
 
diff --git a/gcc/ada/errutil.adb b/gcc/ada/errutil.adb
index 4f5aa21..6747fe5 100644
--- a/gcc/ada/errutil.adb
+++ b/gcc/ada/errutil.adb
@@ -199,6 +199,11 @@ package body Errutil is
          return;
       end if;
 
+      --  Warning, Style and Info attributes are mutually exclusive
+
+      pragma Assert (Boolean'Pos (Is_Warning_Msg) + Boolean'Pos (Is_Info_Msg) +
+        Boolean'Pos (Is_Style_Msg) <= 1);
+
       --  Otherwise build error message object for new message
 
       Errors.Append
@@ -308,15 +313,7 @@ package body Errutil is
       --  Bump appropriate statistics counts
 
       if Errors.Table (Cur_Msg).Info then
-
-         --  Could be (usually is) both "info" and "warning"
-
-         if Errors.Table (Cur_Msg).Warn then
-            Warning_Info_Messages := Warning_Info_Messages + 1;
-            Warnings_Detected := Warnings_Detected + 1;
-         else
-            Report_Info_Messages := Report_Info_Messages + 1;
-         end if;
+         Info_Messages := Info_Messages + 1;
 
       elsif Errors.Table (Cur_Msg).Warn
         or else Errors.Table (Cur_Msg).Style
@@ -553,19 +550,19 @@ package body Errutil is
             Write_Str (" errors");
          end if;
 
-         if Warnings_Detected - Warning_Info_Messages /= 0 then
+         if Warnings_Detected /= 0 then
             Write_Str (", ");
-            Write_Int (Warnings_Detected - Warning_Info_Messages);
+            Write_Int (Warnings_Detected);
             Write_Str (" warning");
 
-            if Warnings_Detected - Warning_Info_Messages /= 1 then
+            if Warnings_Detected /= 1 then
                Write_Char ('s');
             end if;
 
             if Warning_Mode = Treat_As_Error then
                Write_Str (" (treated as error");
 
-               if Warnings_Detected - Warning_Info_Messages /= 1 then
+               if Warnings_Detected /= 1 then
                   Write_Char ('s');
                end if;
 
@@ -595,9 +592,8 @@ package body Errutil is
       --  must not be treated as errors when -gnatwe is in effect.
 
       if Warning_Mode = Treat_As_Error then
-         Total_Errors_Detected :=
-           Total_Errors_Detected + Warnings_Detected - Warning_Info_Messages;
-         Warnings_Detected := Warning_Info_Messages;
+         Total_Errors_Detected := Total_Errors_Detected + Warnings_Detected;
+         Warnings_Detected := 0;
       end if;
 
       --  Prevent displaying the same messages again in the future
@@ -617,8 +613,7 @@ package body Errutil is
       Serious_Errors_Detected := 0;
       Total_Errors_Detected := 0;
       Warnings_Detected := 0;
-      Warning_Info_Messages := 0;
-      Report_Info_Messages := 0;
+      Info_Messages := 0;
       Cur_Msg := No_Error_Msg;
 
       --  Initialize warnings table, if all warnings are suppressed, supply