[Ada] Instruct gnatmake to pass -Oxxx switches to the linker

[Arnaud Charlet]

This makes it so that gnatmake passes -Oxxx switches to the linker in addition
to the compiler.  This is aimed at simplifying the use of LTO in Ada.

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

2010-10-04  Eric Botcazou  <ebotcazou@adacore.com>

	* make.adb (Scan_Make_Arg): Pass -Oxxx switches to the linker as well.
	* gnatlink.adb (Gnatlink): Filter out -Oxxx switches for CLI, RTX and
	AAMP.

-------------- next part --------------
Index: make.adb
===================================================================
--- make.adb	(revision 164906)
+++ make.adb	(working copy)
@@ -8060,12 +8060,12 @@ package body Make is
          elsif Argv (2) = 'L' then
             Add_Switch (Argv, Linker, And_Save => And_Save);
 
-         --  For -gxxxxx, -pg, -mxxx, -fxxx: give the switch to both the
+         --  For -gxxx, -pg, -mxxx, -fxxx, -Oxxx, pass the switch to both the
          --  compiler and the linker (except for -gnatxxx which is only for the
          --  compiler). Some of the -mxxx (for example -m64) and -fxxx (for
          --  example -ftest-coverage for gcov) need to be used when compiling
          --  the binder generated files, and using all these gcc switches for
-         --  the binder generated files should not be a problem.
+         --  them should not be a problem. Pass -Oxxx to the linker for LTO.
 
          elsif
            (Argv (2) = 'g' and then (Argv'Last < 5
@@ -8073,6 +8073,7 @@ package body Make is
              or else Argv (2 .. Argv'Last) = "pg"
              or else (Argv (2) = 'm' and then Argv'Last > 2)
              or else (Argv (2) = 'f' and then Argv'Last > 2)
+             or else (Argv (2) = 'O' and then Argv'Last > 2)
          then
             Add_Switch (Argv, Compiler, And_Save => And_Save);
             Add_Switch (Argv, Linker,   And_Save => And_Save);
Index: gnatlink.adb
===================================================================
--- gnatlink.adb	(revision 164906)
+++ gnatlink.adb	(working copy)
@@ -1965,6 +1965,25 @@ begin
                  or else Linker_Options.Table (J) (1 .. 2) = "-l"
                  or else Linker_Options.Table (J) (1 .. 3) = "-Wl"
                  or else Linker_Options.Table (J) (1 .. 3) = "-sh"
+                 or else Linker_Options.Table (J) (1 .. 2) = "-O"
+                 or else Linker_Options.Table (J) (1 .. 2) = "-g"
+               then
+                  Linker_Options.Table (J .. Linker_Options.Last - 1) :=
+                    Linker_Options.Table (J + 1 .. Linker_Options.Last);
+                  Linker_Options.Decrement_Last;
+                  Num_Args := Num_Args - 1;
+               end if;
+            end loop;
+
+         elsif AAMP_On_Target then
+
+            --  Remove extraneous flags not relevant for AAMP
+
+            for J in reverse Linker_Options.First .. Linker_Options.Last loop
+               if Linker_Options.Table (J)'Length = 0
+                 or else Linker_Options.Table (J) (1 .. 3) = "-Wl"
+                 or else Linker_Options.Table (J) (1 .. 3) = "-sh"
+                 or else Linker_Options.Table (J) (1 .. 2) = "-O"
                  or else Linker_Options.Table (J) (1 .. 2) = "-g"
                then
                   Linker_Options.Table (J .. Linker_Options.Last - 1) :=
@@ -1986,6 +2005,7 @@ begin
                  or else Linker_Options.Table (J) (1 .. 2) = "-l"
                  or else Linker_Options.Table (J) (1 .. 3) = "-Wl"
                  or else Linker_Options.Table (J) (1 .. 3) = "-sh"
+                 or else Linker_Options.Table (J) (1 .. 2) = "-O"
                  or else Linker_Options.Table (J) (1 .. 8) = "-Xlinker"
                  or else Linker_Options.Table (J) (1 .. 9) = "-mthreads"
                then