+2011-05-06 Ivan Maidanski <ivmai@mail.ru>
+
+ * dbg_mlc.c (GC_has_other_debug_info): Change return type to int;
+ return -1 if the object has (or had) debugging info but was
+ marked deallocated.
+ * include/private/dbg_mlc.h (GC_has_other_debug_info): Ditto.
+ * dbg_mlc.c (GC_has_other_debug_info): Update documentation;
+ remove "ohdr" local variable.
+ * dbg_mlc.c (GC_debug_free): Don't call GC_free if the object has
+ probably been deallocated.
+ * dbg_mlc.c (GC_debug_free): Don't actually free the object even
+ in the leak-finding mode if GC_findleak_delay_free.
+ * dbg_mlc.c (GC_print_all_smashed_proc): Print a trailing blank
+ line.
+ * dbg_mlc.c (GC_check_leaked): New function (only unless
+ SHORT_DBG_HDRS).
+ * doc/README.environment (GC_FINDLEAK_DELAY_FREE): Document.
+ * doc/README.macros (GC_FINDLEAK_DELAY_FREE): Ditto.
+ * include/private/dbg_mlc.h (START_FLAG, END_FLAG): Use GC_WORD_C
+ on 64-bit architectures.
+ * include/private/dbg_mlc.h (NOT_MARKED): Remove redundant
+ parentheses.
+ * include/private/dbg_mlc.h (GC_HAS_DEBUG_INFO): Update (due to
+ GC_has_other_debug_info change).
+ * include/private/gc_priv.h (GC_findleak_delay_free): New global
+ variable declaration (unless SHORT_DBG_HDRS).
+ * misc.c (GC_findleak_delay_free): New global variable; recognize
+ GC_FINDLEAK_DELAY_FREE.
+ * misc.c (GC_init): Recognize GC_FINDLEAK_DELAY_FREE environment
+ variable (unless SHORT_DBG_HDRS).
+ * reclaim.c (GC_check_leaked): Declare (unless SHORT_DBG_HDRS).
+ * reclaim.c (GC_add_leaked): Don't add the object to leaked list
+ if marked as deallocated.
+
2011-05-05 Ivan Maidanski <ivmai@mail.ru>
* dbg_mlc.c (GC_has_other_debug_info): Fix punctuation in the
/* odd, which is added by the GC_HAS_DEBUG_INFO macro. */
/* Note that if DBG_HDRS_ALL is set, uncollectable objects */
/* on free lists may not have debug information set. Thus it's */
- /* not always safe to return TRUE, even if the client does */
- /* its part. */
- GC_INNER GC_bool GC_has_other_debug_info(ptr_t p)
+ /* not always safe to return TRUE (1), even if the client does */
+ /* its part. Return -1 if the object with debug info has been */
+ /* marked as deallocated. */
+ GC_INNER int GC_has_other_debug_info(ptr_t p)
{
- oh * ohdr = (oh *)p;
- ptr_t body = (ptr_t)(ohdr + 1);
- word sz = GC_size((ptr_t) ohdr);
+ ptr_t body = (ptr_t)((oh *)p + 1);
+ word sz = GC_size(p);
- if (HBLKPTR((ptr_t)ohdr) != HBLKPTR((ptr_t)body)
+ if (HBLKPTR(p) != HBLKPTR((ptr_t)body)
|| sz < DEBUG_BYTES + EXTRA_BYTES) {
- return(FALSE);
+ return 0;
}
- if (ohdr -> oh_sz == sz) {
- /* Object may have had debug info, but has been deallocated */
- return(FALSE);
+ if (((oh *)p) -> oh_sf != (START_FLAG ^ (word)body)
+ && ((word *)p)[BYTES_TO_WORDS(sz)-1] != (END_FLAG ^ (word)body)) {
+ return 0;
}
- if (ohdr -> oh_sf == (START_FLAG ^ (word)body)) return(TRUE);
- if (((word *)ohdr)[BYTES_TO_WORDS(sz)-1] == (END_FLAG ^ (word)body)) {
- return(TRUE);
+ if (((oh *)p)->oh_sz == sz) {
+ /* Object may have had debug info, but has been deallocated */
+ return -1;
}
- return(FALSE);
+ return 1;
}
#endif /* !SHORT_DBG_HDRS */
ptr_t clobbered = GC_check_annotated_obj((oh *)base);
word sz = GC_size(base);
if (clobbered != 0) {
- GC_print_smashed_obj(((oh *)base) -> oh_sz == sz ?
- "GC_debug_free: found previously deallocated (?) object at" :
- "GC_debug_free: found smashed location at",
- p, clobbered);
GC_have_errors = TRUE;
+ if (((oh *)base) -> oh_sz == sz) {
+ GC_print_smashed_obj(
+ "GC_debug_free: found previously deallocated (?) object at",
+ p, clobbered);
+ return; /* ignore double free */
+ } else {
+ GC_print_smashed_obj("GC_debug_free: found smashed location at",
+ p, clobbered);
+ }
}
- /* Invalidate size */
+ /* Invalidate size (mark the object as deallocated) */
((oh *)base) -> oh_sz = sz;
# endif /* SHORT_DBG_HDRS */
}
- if (GC_find_leak) {
+ if (GC_find_leak
+# ifndef SHORT_DBG_HDRS
+ && ((ptr_t)p - (ptr_t)base != sizeof(oh) || !GC_findleak_delay_free)
+# endif
+ ) {
GC_free(base);
} else {
hdr * hhdr = HDR(p);
GC_smashed[i] = 0;
}
GC_n_smashed = 0;
+ GC_err_printf("\n");
}
/* Check all marked objects in the given block for validity */
GC_apply_to_all_blocks(GC_check_heap_block, 0);
}
+GC_INNER GC_bool GC_check_leaked(ptr_t base)
+{
+ size_t i;
+ size_t obj_sz;
+ word *p;
+
+ if (
+# if defined(KEEP_BACK_PTRS) || defined(MAKE_BACK_GRAPH)
+ (*(word *)base & 1) != 0 &&
+# endif
+ GC_has_other_debug_info(base) >= 0)
+ return TRUE; /* object has leaked */
+
+ /* Validate freed object's content. */
+ p = (word *)(base + sizeof(oh));
+ obj_sz = BYTES_TO_WORDS(HDR(base)->hb_sz - sizeof(oh));
+ for (i = 0; i < obj_sz; ++i)
+ if (p[i] != GC_FREED_MEM_MARKER) {
+ GC_set_mark_bit(base); /* do not reclaim it in this cycle */
+ GC_add_smashed((ptr_t)(&p[i])); /* alter-after-free detected */
+ break; /* don't report any other smashed locations in the object */
+ }
+
+ return FALSE; /* GC_debug_free() has been called */
+}
+
#endif /* !SHORT_DBG_HDRS */
struct closure {
#ifndef _DBG_MLC_H
#define _DBG_MLC_H
-# include "gc_priv.h"
-# ifdef KEEP_BACK_PTRS
-# include "gc_backptr.h"
-# endif
+#include "gc_priv.h"
+#ifdef KEEP_BACK_PTRS
+# include "gc_backptr.h"
+#endif
-# define START_FLAG ((word)0xfedcedcb)
-# define END_FLAG ((word)0xbcdecdef)
+#if CPP_WORDSZ == 32
+# define START_FLAG (word)0xfedcedcb
+# define END_FLAG (word)0xbcdecdef
+#else
+# define START_FLAG GC_WORD_C(0xFEDCEDCBfedcedcb)
+# define END_FLAG GC_WORD_C(0xBCDECDEFbcdecdef)
+#endif
/* Stored both one past the end of user object, and one before */
/* the end of the object as seen by the allocator. */
-# if defined(KEEP_BACK_PTRS) || defined(PRINT_BLACK_LIST) \
- || defined(MAKE_BACK_GRAPH)
- /* Pointer "source"s that aren't real locations. */
- /* Used in oh_back_ptr fields and as "source" */
- /* argument to some marking functions. */
-# define NOT_MARKED (ptr_t)(0)
-# define MARKED_FOR_FINALIZATION ((ptr_t)(word)2)
- /* Object was marked because it is finalizable. */
-# define MARKED_FROM_REGISTER ((ptr_t)(word)4)
- /* Object was marked from a register. Hence the */
- /* source of the reference doesn't have an address. */
-# endif /* KEEP_BACK_PTRS || PRINT_BLACK_LIST */
+#if defined(KEEP_BACK_PTRS) || defined(PRINT_BLACK_LIST) \
+ || defined(MAKE_BACK_GRAPH)
+ /* Pointer "source"s that aren't real locations. */
+ /* Used in oh_back_ptr fields and as "source" */
+ /* argument to some marking functions. */
+# define NOT_MARKED (ptr_t)0
+# define MARKED_FOR_FINALIZATION ((ptr_t)(word)2)
+ /* Object was marked because it is finalizable. */
+# define MARKED_FROM_REGISTER ((ptr_t)(word)4)
+ /* Object was marked from a register. Hence the */
+ /* source of the reference doesn't have an address. */
+#endif /* KEEP_BACK_PTRS || PRINT_BLACK_LIST */
/* Object header */
typedef struct {
-# if defined(KEEP_BACK_PTRS) || defined(MAKE_BACK_GRAPH)
- /* We potentially keep two different kinds of back */
- /* pointers. KEEP_BACK_PTRS stores a single back */
- /* pointer in each reachable object to allow reporting */
- /* of why an object was retained. MAKE_BACK_GRAPH */
- /* builds a graph containing the inverse of all */
- /* "points-to" edges including those involving */
- /* objects that have just become unreachable. This */
- /* allows detection of growing chains of unreachable */
- /* objects. It may be possible to eventually combine */
- /* both, but for now we keep them separate. Both */
- /* kinds of back pointers are hidden using the */
- /* following macros. In both cases, the plain version */
- /* is constrained to have an least significant bit of 1,*/
- /* to allow it to be distinguished from a free list */
- /* link. This means the plain version must have an */
- /* lsb of 0. */
- /* Note that blocks dropped by black-listing will */
- /* also have the lsb clear once debugging has */
- /* started. */
- /* We're careful never to overwrite a value with lsb 0. */
-# if ALIGNMENT == 1
- /* Fudge back pointer to be even. */
-# define HIDE_BACK_PTR(p) GC_HIDE_POINTER(~1 & (GC_word)(p))
-# else
-# define HIDE_BACK_PTR(p) GC_HIDE_POINTER(p)
-# endif
-
-# ifdef KEEP_BACK_PTRS
- GC_hidden_pointer oh_back_ptr;
-# endif
-# ifdef MAKE_BACK_GRAPH
- GC_hidden_pointer oh_bg_ptr;
-# endif
-# if defined(KEEP_BACK_PTRS) != defined(MAKE_BACK_GRAPH)
- /* Keep double-pointer-sized alignment. */
- word oh_dummy;
-# endif
+# if defined(KEEP_BACK_PTRS) || defined(MAKE_BACK_GRAPH)
+ /* We potentially keep two different kinds of back */
+ /* pointers. KEEP_BACK_PTRS stores a single back */
+ /* pointer in each reachable object to allow reporting */
+ /* of why an object was retained. MAKE_BACK_GRAPH */
+ /* builds a graph containing the inverse of all */
+ /* "points-to" edges including those involving */
+ /* objects that have just become unreachable. This */
+ /* allows detection of growing chains of unreachable */
+ /* objects. It may be possible to eventually combine */
+ /* both, but for now we keep them separate. Both */
+ /* kinds of back pointers are hidden using the */
+ /* following macros. In both cases, the plain version */
+ /* is constrained to have an least significant bit of 1, */
+ /* to allow it to be distinguished from a free list */
+ /* link. This means the plain version must have an */
+ /* lsb of 0. */
+ /* Note that blocks dropped by black-listing will */
+ /* also have the lsb clear once debugging has */
+ /* started. */
+ /* We're careful never to overwrite a value with lsb 0. */
+# if ALIGNMENT == 1
+ /* Fudge back pointer to be even. */
+# define HIDE_BACK_PTR(p) GC_HIDE_POINTER(~1 & (GC_word)(p))
+# else
+# define HIDE_BACK_PTR(p) GC_HIDE_POINTER(p)
+# endif
+# ifdef KEEP_BACK_PTRS
+ GC_hidden_pointer oh_back_ptr;
+# endif
+# ifdef MAKE_BACK_GRAPH
+ GC_hidden_pointer oh_bg_ptr;
# endif
- const char * oh_string; /* object descriptor string */
- word oh_int; /* object descriptor integers */
-# ifdef NEED_CALLINFO
- struct callinfo oh_ci[NFRAMES];
+# if defined(KEEP_BACK_PTRS) != defined(MAKE_BACK_GRAPH)
+ /* Keep double-pointer-sized alignment. */
+ word oh_dummy;
# endif
-# ifndef SHORT_DBG_HDRS
- word oh_sz; /* Original malloc arg. */
- word oh_sf; /* start flag */
-# endif /* SHORT_DBG_HDRS */
+# endif
+ const char * oh_string; /* object descriptor string */
+ word oh_int; /* object descriptor integers */
+# ifdef NEED_CALLINFO
+ struct callinfo oh_ci[NFRAMES];
+# endif
+# ifndef SHORT_DBG_HDRS
+ word oh_sz; /* Original malloc arg. */
+ word oh_sf; /* start flag */
+# endif /* SHORT_DBG_HDRS */
} oh;
/* The size of the above structure is assumed not to de-align things, */
/* and to be a multiple of the word length. */
#ifdef SHORT_DBG_HDRS
-# define DEBUG_BYTES (sizeof (oh))
-# define UNCOLLECTABLE_DEBUG_BYTES DEBUG_BYTES
+# define DEBUG_BYTES (sizeof (oh))
+# define UNCOLLECTABLE_DEBUG_BYTES DEBUG_BYTES
#else
- /* Add space for END_FLAG, but use any extra space that was already */
- /* added to catch off-the-end pointers. */
- /* For uncollectable objects, the extra byte is not added. */
-# define UNCOLLECTABLE_DEBUG_BYTES (sizeof (oh) + sizeof (word))
-# define DEBUG_BYTES (UNCOLLECTABLE_DEBUG_BYTES - EXTRA_BYTES)
+ /* Add space for END_FLAG, but use any extra space that was already */
+ /* added to catch off-the-end pointers. */
+ /* For uncollectable objects, the extra byte is not added. */
+# define UNCOLLECTABLE_DEBUG_BYTES (sizeof (oh) + sizeof (word))
+# define DEBUG_BYTES (UNCOLLECTABLE_DEBUG_BYTES - EXTRA_BYTES)
#endif
/* Round bytes to words without adding extra byte at end. */
/* PRINT_CALL_CHAIN prints the call chain stored in an object */
/* to stderr. It requires that we do not hold the lock. */
#if defined(SAVE_CALL_CHAIN)
- struct callinfo;
- GC_INNER void GC_save_callers(struct callinfo info[NFRAMES]);
- GC_INNER void GC_print_callers(struct callinfo info[NFRAMES]);
-# define ADD_CALL_CHAIN(base, ra) GC_save_callers(((oh *)(base)) -> oh_ci)
-# define PRINT_CALL_CHAIN(base) GC_print_callers(((oh *)(base)) -> oh_ci)
+ struct callinfo;
+ GC_INNER void GC_save_callers(struct callinfo info[NFRAMES]);
+ GC_INNER void GC_print_callers(struct callinfo info[NFRAMES]);
+# define ADD_CALL_CHAIN(base, ra) GC_save_callers(((oh *)(base)) -> oh_ci)
+# define PRINT_CALL_CHAIN(base) GC_print_callers(((oh *)(base)) -> oh_ci)
#elif defined(GC_ADD_CALLER)
- struct callinfo;
- GC_INNER void GC_print_callers(struct callinfo info[NFRAMES]);
-# define ADD_CALL_CHAIN(base, ra) ((oh *)(base)) -> oh_ci[0].ci_pc = (ra)
-# define PRINT_CALL_CHAIN(base) GC_print_callers(((oh *)(base)) -> oh_ci)
+ struct callinfo;
+ GC_INNER void GC_print_callers(struct callinfo info[NFRAMES]);
+# define ADD_CALL_CHAIN(base, ra) ((oh *)(base)) -> oh_ci[0].ci_pc = (ra)
+# define PRINT_CALL_CHAIN(base) GC_print_callers(((oh *)(base)) -> oh_ci)
#else
-# define ADD_CALL_CHAIN(base, ra)
-# define PRINT_CALL_CHAIN(base)
+# define ADD_CALL_CHAIN(base, ra)
+# define PRINT_CALL_CHAIN(base)
#endif
-# ifdef GC_ADD_CALLER
-# define OPT_RA ra,
-# else
-# define OPT_RA
-# endif
-
+#ifdef GC_ADD_CALLER
+# define OPT_RA ra,
+#else
+# define OPT_RA
+#endif
/* Check whether object with base pointer p has debugging info */
/* p is assumed to point to a legitimate object in our part */
/* of the heap. */
#ifdef SHORT_DBG_HDRS
-# define GC_has_other_debug_info(p) TRUE
+# define GC_has_other_debug_info(p) 1
#else
- GC_INNER GC_bool GC_has_other_debug_info(ptr_t p);
+ GC_INNER int GC_has_other_debug_info(ptr_t p);
#endif
#if defined(KEEP_BACK_PTRS) || defined(MAKE_BACK_GRAPH)
# define GC_HAS_DEBUG_INFO(p) \
- ((*((word *)p) & 1) && GC_has_other_debug_info(p))
+ ((*((word *)p) & 1) && GC_has_other_debug_info(p) > 0)
#else
-# define GC_HAS_DEBUG_INFO(p) GC_has_other_debug_info(p)
+# define GC_HAS_DEBUG_INFO(p) (GC_has_other_debug_info(p) > 0)
#endif
#endif /* _DBG_MLC_H */
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