From 5f486660101ab09d50fa3bb9a10555f12722f39f Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Tue, 12 Feb 2019 14:28:07 -0700 Subject: [PATCH] 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, std::allocator > const&, std::__cxx11::basic_string, std::allocator > 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 Tom Tromey * 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) : 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) : Remove bp_location_ops parameter. <~bp_location>: Add destructor. : Remove. --- gdb/ChangeLog | 18 ++++++++++++++++++ gdb/ada-lang.c | 24 +++--------------------- gdb/breakpoint.c | 20 ++++---------------- gdb/breakpoint.h | 18 +++--------------- 4 files changed, 28 insertions(+), 52 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index bb27f74..11667ae 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,21 @@ +2019-02-15 Philippe Waroquiers + Tom Tromey + + * 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) + : 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) : Remove bp_location_ops + parameter. + <~bp_location>: Add destructor. + : Remove. + 2019-02-14 Thomas Schwinge Pedro Alves diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c index a878d4d..602facb 100644 --- a/gdb/ada-lang.c +++ b/gdb/ada-lang.c @@ -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 diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c index 67d83e6..9be99ff 100644 --- a/gdb/breakpoint.c +++ b/gdb/breakpoint.c @@ -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 diff --git a/gdb/breakpoint.h b/gdb/breakpoint.h index 8c8c66a..a91e3e3 100644 --- a/gdb/breakpoint.h +++ b/gdb/breakpoint.h @@ -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; -- 2.7.4