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.