Memory Leaks with pointers

[Tricky]

Consider the following:
type a_t;
type a_t_ptr is access a_t;

type b_t;
type b_t_ptr is access b_t;

type a_t is array(integer range <&gt of integer;
type b_t is array(integer range <&gt of a_t_ptr;

begin

process
variable P : b_t_ptr;
begin

P := new b_t(1 to 10);

for i in 1 to 10 loop
p(i) = new a_t(1 to 10);
end loop;

DEALLOCATE(P);
wait;
end process;

have I just caused a memory leak by not deallocating all the elements
in the top level array? would you have to quit the simulator to free
it again, or just end the simulation?

 

[Jonathan Bromley]

On Tue, 5 Aug 2008 09:24:00 -0700 (PDT),
Tricky wrote:

Consider the following:
type a_t;
type a_t_ptr is access a_t;

type b_t;
type b_t_ptr is access b_t;

type a_t is array(integer range <&gt of integer;
type b_t is array(integer range <&gt of a_t_ptr;

begin

process
variable P : b_t_ptr;
begin

P := new b_t(1 to 10);

for i in 1 to 10 loop
p(i) = new a_t(1 to 10);
end loop;

DEALLOCATE(P);
wait;
end process;

have I just caused a memory leak by not deallocating all the elements
in the top level array?

I believe so.

would you have to quit the simulator to free
it again, or just end the simulation?

Depends on the simulator, I guess. Simulators do so much
fooling around with memory allocation anyways that I've never
found a way to detect that sort of thing reliably. Whenever
I build hierarchical dynamically-allocated structures, I
always provide them with a delete() method that deletes
all their component objects before deallocating the
top level object. Maybe that's just over-paranoid,
but I've survived to this old age mainly by being
paranoid and I don't plan on changing now
--
Jonathan Bromley, Consultant

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