prj.ads, [...] (Queue.Insert): now also inserts the "roots" for a main.

2011-08-03  Emmanuel Briot  <briot@adacore.com>

	* prj.ads, makeutl.adb, makeutl.ads (Queue.Insert): now also inserts
	the "roots" for a main.
	(Fill_From_Project): add support for aggregate projects. Main units
	in aggregated projects are now automatically added in the list of
	files to build (although this fails later on in gprbuild, because
	these files are not using the root proejct tree, so this needs
	further cleanup)
	* gcc-interface/Make-lang.in: Update dependencies.

From-SVN: r177287

gcc/ada/ChangeLog

+2011-08-03  Emmanuel Briot  <briot@adacore.com>
+
+	* prj.ads, makeutl.adb, makeutl.ads (Queue.Insert): now also inserts
+	the "roots" for a main.
+	(Fill_From_Project): add support for aggregate projects. Main units
+	in aggregated projects are now automatically added in the list of
+	files to build (although this fails later on in gprbuild, because
+	these files are not using the root proejct tree, so this needs
+	further cleanup)
+	* gcc-interface/Make-lang.in: Update dependencies.
+
 2011-08-03  Yannick Moy  <moy@adacore.com>
 
 	* sem_ch4.adb (Analyze_Conditional_Expression): only allow boolean

gcc/ada/makeutl.ads

@@ -245,15 +245,21 @@ package Makeutl is
       File      : File_Name_Type;  --  Always canonical casing
       Index     : Int := 0;
       Location  : Source_Ptr := No_Location;
+
       Source    : Prj.Source_Id := No_Source;
+      Project   : Project_Id;
+      Tree      : Project_Tree_Ref;
    end record;
-   No_Main_Info : constant Main_Info := (No_File, 0, No_Location, No_Source);
+   No_Main_Info : constant Main_Info :=
+     (No_File, 0, No_Location, No_Source, No_Project, null);
 
    package Mains is
       procedure Add_Main
         (Name     : String;
          Index    : Int := 0;
-         Location : Source_Ptr := No_Location);
+         Location : Source_Ptr := No_Location;
+         Project  : Project_Id := No_Project;
+         Tree     : Project_Tree_Ref := null);
       --  Add one main to the table.
       --  This is in general used to add the main files specified on the
       --  command line.
@@ -261,6 +267,10 @@ package Makeutl is
       --  within the source is concerned.
       --  Location is the location within the project file (if a project file
       --  is used).
+      --  Project and Tree indicate to which project the main should belong.
+      --  In particular, for aggregate projects, this isn't necessarily the
+      --  main project tree. These can be set to No_Project and null when not
+      --  using projects.
 
       procedure Delete;
       --  Empty the table
@@ -290,8 +300,7 @@ package Makeutl is
          Project_Tree : Project_Tree_Ref);
       --  If no main was already added (presumably from the command line), add
       --  the main units from root_project (or in the case of an aggregate
-      --  project from all the
-      --  aggregated projects).
+      --  project from all the aggregated projects).
       --
       --  If some main units were already added from the command line, check
       --  that they all belong to the root project, and that they are full
@@ -314,7 +323,8 @@ package Makeutl is
          record
             case Format is
             when Format_Gprbuild =>
-               Id : Source_Id := null;
+               Tree : Project_Tree_Ref := null;
+               Id   : Source_Id := null;
 
             when Format_Gnatmake =>
                File      : File_Name_Type := No_File;
@@ -352,11 +362,18 @@ package Makeutl is
       --  Returns True if the queue is empty or if all object directories are
       --  busy.
 
-      procedure Insert (Source  : Source_Info);
-      function Insert (Source  : Source_Info) return Boolean;
+      procedure Insert (Source  : Source_Info; With_Roots : Boolean := False);
+      function Insert
+        (Source  : Source_Info; With_Roots : Boolean := False) return Boolean;
       --  Insert source in the queue.
       --  The second version returns False if the Source was already marked in
       --  the queue.
+      --  If With_Roots is True and the source is in Format_Gprbuild mode (ie
+      --  with a project), this procedure also includes the "Roots" for this
+      --  main, ie all the other files that must be included in the library or
+      --  binary (in particular to combine Ada and C files connected through
+      --  pragma Export/Import). When the roots are computed, they are also
+      --  stored in the corresponding Source_Id for later reuse by the binder.
 
       procedure Insert_Project_Sources
         (Project      : Project_Id;

gcc/ada/prj.ads

@@ -660,6 +660,17 @@ package Prj is
    No_Unit_Index : constant Unit_Index := null;
    --  Used to indicate a null entry for no unit
 
+   type Source_Roots;
+   type Roots_Access is access Source_Roots;
+   type Source_Roots is record
+      Root : Source_Id;
+      Next : Roots_Access;
+   end record;
+   --  A list to store the roots associated with a main unit. These are the
+   --  files that need to linked along with the main (for instance a C file
+   --  corresponding to an Ada file). In general, these are dependencies that
+   --  cannot be computed automatically by the builder.
+
    --  Structure to define source data
 
    type Source_Data is record
@@ -784,6 +795,9 @@ package Prj is
       Next_With_File_Name : Source_Id := No_Source;
       --  Link to another source with the same base file name
 
+      Roots : Roots_Access := null;
+      --  The roots for a main unit
+
    end record;
 
    No_Source_Data : constant Source_Data :=
@@ -821,7 +835,8 @@ package Prj is
                        Naming_Exception       => False,
                        Duplicate_Unit         => False,
                        Next_In_Lang           => No_Source,
-                       Next_With_File_Name    => No_Source);
+                       Next_With_File_Name    => No_Source,
+                       Roots                  => null);
 
    package Source_Files_Htable is new Simple_HTable
      (Header_Num => Header_Num,