When the type of an object is a CPP untagged type and the object initialization
requires calling its default C++ constructor, the Ada compiler did not
generate the call to a C++ constructor which has all parameters with
defaults (and hence it covers the default C++ constructor).
// c_class.h
class Tester {
public:
Tester(unsigned int a_num = 5, char* a_className = 0);
};
// c_class.cc
#include "c_class.h"
#include <iostream>
Tester::Tester(unsigned int a_num, char* a_className) {
std::cout << " ctor Tester called " << a_num << ":";
if (a_className == 0) {
std::cout << "null";
} else {
std::cout << a_className;
}
std::cout << std::endl;
}
-- c_class_h.ads
with Interfaces.C; use Interfaces.C;
with Interfaces.C.Strings;
package c_class_h is
package Class_Tester is
type Tester is limited record
null;
end record;
pragma Import (CPP, Tester);
function New_Tester -- Modified by hand
(a_num : unsigned := 5;
a_className : Interfaces.C.Strings.chars_ptr
:= Interfaces.C.Strings.Null_Ptr)
return Tester; -- c_class.h:3
pragma CPP_Constructor (New_Tester, "_ZN6TesterC1EjPc");
end;
use Class_Tester;
end c_class_h;
-- main.adb
with c_class_h; use c_class_h;
procedure Main is
use Class_Tester;
Ptr : access Tester := new Tester; -- TEST
pragma Unreferenced (Ptr);
begin
null;
end main;
-- ada2cpp.gpr
project Ada2Cppc is
for Languages use ("Ada", "C++");
for Main use ("main.adb");
package Naming is
for Implementation_Suffix ("C++") use ".cc";
end Naming;
for Source_Dirs use (".");
for Object_Dir use "obj";
package Compiler is
for Default_Switches ("ada") use
("-g", "-gnato", "-gnatwa", "-gnatQ", "-gnat05", "-gnatD");
end Compiler;
package Builder is
for Default_Switches ("ada") use ("-g");
end Builder;
package Ide is
for Compiler_Command ("ada") use "gnatmake";
for Compiler_Command ("c") use "gcc";
end Ide;
end Ada2Cppc;
Command: gprbuild -q -P ada2cppc.gpr; obj/main
Output:
ctor Tester called 5:null
Tested on x86_64-pc-linux-gnu, committed on trunk
2012-10-03 Javier Miranda <mira...@adacore.com>
* exp_disp.adb (Set_CPP_Constructors_Old): Handle constructor of
untagged type that has all its parameters with defaults and hence it
covers the default constructor.
Index: exp_disp.adb
===================================================================
--- exp_disp.adb (revision 192025)
+++ exp_disp.adb (working copy)
@@ -8459,6 +8459,8 @@
P : Node_Id;
Parms : List_Id;
+ Covers_Default_Constructor : Entity_Id := Empty;
+
begin
-- Look for the constructor entities
@@ -8490,7 +8492,8 @@
Make_Defining_Identifier (Loc,
Chars (Defining_Identifier (P))),
Parameter_Type =>
- New_Copy_Tree (Parameter_Type (P))));
+ New_Copy_Tree (Parameter_Type (P)),
+ Expression => New_Copy_Tree (Expression (P))));
Next (P);
end loop;
end if;
@@ -8508,6 +8511,17 @@
Set_Convention (Init, Convention_CPP);
Set_Is_Public (Init);
Set_Has_Completion (Init);
+
+ -- If this constructor has parameters and all its parameters
+ -- have defaults then it covers the default constructor. The
+ -- semantic analyzer ensures that only one constructor with
+ -- defaults covers the default constructor.
+
+ if Present (Parameter_Specifications (Parent (E)))
+ and then Needs_No_Actuals (E)
+ then
+ Covers_Default_Constructor := Init;
+ end if;
end if;
Next_Entity (E);
@@ -8519,6 +8533,49 @@
if not Found then
Set_Is_Abstract_Type (Typ);
end if;
+
+ -- Handle constructor that has all its parameters with defaults and
+ -- hence it covers the default constructor. We generate a wrapper IP
+ -- which calls the covering constructor.
+
+ if Present (Covers_Default_Constructor) then
+ declare
+ Body_Stmts : List_Id;
+ Wrapper_Id : Entity_Id;
+ Wrapper_Body_Node : Node_Id;
+ begin
+ Loc := Sloc (Covers_Default_Constructor);
+
+ Body_Stmts := New_List (
+ Make_Procedure_Call_Statement (Loc,
+ Name => New_Reference_To (Covers_Default_Constructor, Loc),
+ Parameter_Associations => New_List (
+ Make_Identifier (Loc, Name_uInit))));
+
+ Wrapper_Id := Make_Defining_Identifier (Loc,
+ Make_Init_Proc_Name (Typ));
+
+ Wrapper_Body_Node :=
+ Make_Subprogram_Body (Loc,
+ Specification =>
+ Make_Procedure_Specification (Loc,
+ Defining_Unit_Name => Wrapper_Id,
+ Parameter_Specifications => New_List (
+ Make_Parameter_Specification (Loc,
+ Defining_Identifier =>
+ Make_Defining_Identifier (Loc, Name_uInit),
+ Parameter_Type =>
+ New_Reference_To (Typ, Loc)))),
+ Declarations => No_List,
+ Handled_Statement_Sequence =>
+ Make_Handled_Sequence_Of_Statements (Loc,
+ Statements => Body_Stmts,
+ Exception_Handlers => No_List));
+
+ Discard_Node (Wrapper_Body_Node);
+ Set_Init_Proc (Typ, Wrapper_Id);
+ end;
+ end if;
end Set_CPP_Constructors_Old;
-- Local variables
