C++-ify bp_location

Philippe noticed a memory leak coming from ada_catchpoint_location --
it was not freeing the "function_name" member from its base class:

==14141== 114 bytes in 4 blocks are definitely lost in loss record 1,055 of 3,424
==14141==    at 0x4C2BE6D: malloc (vg_replace_malloc.c:309)
==14141==    by 0x405107: xmalloc (common-utils.c:44)
==14141==    by 0x7563F9: xstrdup (xstrdup.c:34)
==14141==    by 0x3B82B3: set_breakpoint_location_function(bp_location*, int) (breakpoint.c:7156)
==14141==    by 0x3C112B: add_location_to_breakpoint(breakpoint*, symtab_and_line const*) (breakpoint.c:8609)
==14141==    by 0x3C127A: init_raw_breakpoint(breakpoint*, gdbarch*, symtab_and_line, bptype, breakpoint_ops const*) (breakpoint.c:7187)
==14141==    by 0x3C1B52: init_ada_exception_breakpoint(breakpoint*, gdbarch*, symtab_and_line, char const*, breakpoint_ops const*, int, int, int) (breakpoint.c:11262)
==14141==    by 0x381C2E: create_ada_exception_catchpoint(gdbarch*, ada_exception_catchpoint_kind, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, int, int, int) (ada-lang.c:13255)

This patch fixes the problem by further C++-ifying bp_location.  In
particular, bp_location_ops is now removed, and the "dtor" function
pointer is replaced with an ordinary destructor.

gdb/ChangeLog
2019-02-15  Philippe Waroquiers  <philippe.waroquiers@skynet.be>
	    Tom Tromey  <tromey@adacore.com>

	* breakpoint.c (~bp_location): Rename from bp_location_dtor.
	(bp_location_ops): Remove.
	(base_breakpoint_allocate_location): Update.
	(free_bp_location): Update.
	* ada-lang.c (class ada_catchpoint_location)
	<ada_catchpoint_location>: Remove ops parameter.
	(ada_catchpoint_location_dtor): Remove.
	(ada_catchpoint_location_ops): Remove.
	(allocate_location_exception): Update.
	* breakpoint.h (struct bp_location_ops): Remove.
	(class bp_location) <bp_location>: Remove bp_location_ops
	parameter.
	<~bp_location>: Add destructor.
	<ops>: Remove.
This commit is contained in:
Tom Tromey 2019-02-12 14:28:07 -07:00
parent 91d78b8179
commit 5f48666010
4 changed files with 28 additions and 52 deletions

View file

@ -1,3 +1,21 @@
2019-02-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
Tom Tromey <tromey@adacore.com>
* breakpoint.c (~bp_location): Rename from bp_location_dtor.
(bp_location_ops): Remove.
(base_breakpoint_allocate_location): Update.
(free_bp_location): Update.
* ada-lang.c (class ada_catchpoint_location)
<ada_catchpoint_location>: Remove ops parameter.
(ada_catchpoint_location_dtor): Remove.
(ada_catchpoint_location_ops): Remove.
(allocate_location_exception): Update.
* breakpoint.h (struct bp_location_ops): Remove.
(class bp_location) <bp_location>: Remove bp_location_ops
parameter.
<~bp_location>: Add destructor.
<ops>: Remove.
2019-02-14 Thomas Schwinge <thomas@codesourcery.com>
Pedro Alves <palves@redhat.com>

View file

@ -12396,8 +12396,8 @@ static std::string ada_exception_catchpoint_cond_string
class ada_catchpoint_location : public bp_location
{
public:
ada_catchpoint_location (const bp_location_ops *ops, breakpoint *owner)
: bp_location (ops, owner)
ada_catchpoint_location (breakpoint *owner)
: bp_location (owner)
{}
/* The condition that checks whether the exception that was raised
@ -12406,24 +12406,6 @@ public:
expression_up excep_cond_expr;
};
/* Implement the DTOR method in the bp_location_ops structure for all
Ada exception catchpoint kinds. */
static void
ada_catchpoint_location_dtor (struct bp_location *bl)
{
struct ada_catchpoint_location *al = (struct ada_catchpoint_location *) bl;
al->excep_cond_expr.reset ();
}
/* The vtable to be used in Ada catchpoint locations. */
static const struct bp_location_ops ada_catchpoint_location_ops =
{
ada_catchpoint_location_dtor
};
/* An instance of this type is used to represent an Ada catchpoint. */
struct ada_catchpoint : public breakpoint
@ -12493,7 +12475,7 @@ static struct bp_location *
allocate_location_exception (enum ada_exception_catchpoint_kind ex,
struct breakpoint *self)
{
return new ada_catchpoint_location (&ada_catchpoint_location_ops, self);
return new ada_catchpoint_location (self);
}
/* Implement the RE_SET method in the breakpoint_ops structure for all

View file

@ -6958,13 +6958,10 @@ adjust_breakpoint_address (struct gdbarch *gdbarch,
}
}
bp_location::bp_location (const bp_location_ops *ops, breakpoint *owner)
bp_location::bp_location (breakpoint *owner)
{
bp_location *loc = this;
gdb_assert (ops != NULL);
loc->ops = ops;
loc->owner = owner;
loc->cond_bytecode = NULL;
loc->shlib_disabled = 0;
@ -7033,7 +7030,6 @@ allocate_bp_location (struct breakpoint *bpt)
static void
free_bp_location (struct bp_location *loc)
{
loc->ops->dtor (loc);
delete loc;
}
@ -12166,19 +12162,11 @@ say_where (struct breakpoint *b)
}
}
/* Default bp_location_ops methods. */
static void
bp_location_dtor (struct bp_location *self)
bp_location::~bp_location ()
{
xfree (self->function_name);
xfree (function_name);
}
static const struct bp_location_ops bp_location_ops =
{
bp_location_dtor
};
/* Destructor for the breakpoint base class. */
breakpoint::~breakpoint ()
@ -12191,7 +12179,7 @@ breakpoint::~breakpoint ()
static struct bp_location *
base_breakpoint_allocate_location (struct breakpoint *self)
{
return new bp_location (&bp_location_ops, self);
return new bp_location (self);
}
static void

View file

@ -301,31 +301,19 @@ enum bp_loc_type
bp_loc_other /* Miscellaneous... */
};
/* This structure is a collection of function pointers that, if
available, will be called instead of performing the default action
for this bp_loc_type. */
struct bp_location_ops
{
/* Destructor. Releases everything from SELF (but not SELF
itself). */
void (*dtor) (struct bp_location *self);
};
class bp_location
{
public:
bp_location () = default;
bp_location (const bp_location_ops *ops, breakpoint *owner);
bp_location (breakpoint *owner);
virtual ~bp_location ();
/* Chain pointer to the next breakpoint location for
the same parent breakpoint. */
bp_location *next = NULL;
/* Methods associated with this location. */
const bp_location_ops *ops = NULL;
/* The reference count. */
int refc = 0;