old-cross-binutils/gdb/testsuite/gdb.ada/float_param/pck.adb
Joel Brobecker 4d804846db [dwarf] Mark all functions as prototyped except C functions.
This makes sure that the types of the arguments are taken into account
when performing an inferior function call to a non-C (or C-like)
function.  In particular, this makes sure that the arguments are
appropriatly converted to the correct type.

For instance, on x86_64-linux, with the following Ada code:

   procedure Set_Float (F : Float) is
   begin
      Global_Float := F;
   end Set_Float;

The following sequence shows that Float arguments are incorrectly
passed (Ada's Float type is the equivalent of type "float" in C):

    (gdb) call set_float (2.0)
    (gdb) print global_float
    $1 = 0.0

Putting a breakpoint inside set_float to inspect the value of
register xmm0 gives the first hint of the problem:

    (gdb) p $xmm0
    $2 = (v4_float => (0 => 0.0, 2.0, 0.0, 0.0),
          v2_double => (0 => 2.0, 0.0),
    [...]

It shows that the argument was passed as a double.

The code responsible for doing appropriate type conversions
for the arguments (value_arg_coerce) found that our function
was not prototyped, and thus could not use typing information
for the arguments. Instead, it defaulted to the value of "set
coerce-float-to-double", which by default is true, to determine
the argument type.

This patch fixes the problem by setting the PROTOTYPE flag
for all functions of any language except C and Objective C.

gdb/ChangeLog:

        * dwarf2read.c (prototyped_function_p): New function.
        (read_subroutine_type): Use it.

gdb/testsuite/ChangeLog:

        * gdb.ada/float_param: New testcase.
2013-05-20 09:45:13 +00:00

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Ada

-- Copyright 2013 Free Software Foundation, Inc.
--
-- This program is free software; you can redistribute it and/or modify
-- it under the terms of the GNU General Public License as published by
-- the Free Software Foundation; either version 3 of the License, or
-- (at your option) any later version.
--
-- This program is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-- GNU General Public License for more details.
--
-- You should have received a copy of the GNU General Public License
-- along with this program. If not, see <http://www.gnu.org/licenses/>.
package body Pck is
procedure Set_Float (F : Float) is
begin
Global_Float := F;
end Set_Float;
procedure Set_Double (Dummy : Integer; D : Long_Float) is
begin
Global_Double := D;
end Set_Double;
procedure Set_Long_Double (Dummy : Integer;
DS : Small_Struct;
LD : Long_Long_Float) is
begin
Global_Long_Double := LD;
end Set_Long_Double;
end Pck;