</para>
</listitem>
</varlistentry>
+ <varlistentry>
+ <term>
+ <option>
+ <![CDATA[--free-is-write=<yes|no> [default: no]]]>
+ </option>
+ </term>
+ <listitem>
+ <para>
+ Whether to report races between accessing memory and freeing
+ memory. Enabling this option may cause DRD to run slightly
+ slower. Notes:
+ <itemizedlist>
+ <listitem>
+ <para>
+ Don't enable this option when using custom memory allocators
+ that use
+ the <computeroutput>VG_USERREQ__MALLOCLIKE_BLOCK</computeroutput>
+ and <computeroutput>VG_USERREQ__FREELIKE_BLOCK</computeroutput>
+ because that would result in false positives.
+ </para>
+ </listitem>
+ <listitem>
+ <para>Don't enable this option when using reference-counted
+ objects because that will result in false positives, even when
+ that code has been annotated properly with
+ <computeroutput>ANNOTATE_HAPPENS_BEFORE</computeroutput>
+ and <computeroutput>ANNOTATE_HAPPENS_AFTER</computeroutput>. See
+ e.g. the output of the following command for an example:
+ <computeroutput>valgrind --tool=drd --free-is-write=yes
+ drd/tests/annotate_smart_pointer</computeroutput>.
+ </para>
+ </listitem>
+ </itemizedlist>
+ </para>
+ </listitem>
+ </varlistentry>
<varlistentry>
<term>
<option>
/* Local variables. */
+static Bool s_free_is_write = False;
static Bool s_print_stats = False;
static Bool s_var_info = False;
static Bool s_show_stack_usage = False;
if VG_BOOL_CLO(arg, "--check-stack-var", check_stack_accesses) {}
else if VG_BOOL_CLO(arg, "--drd-stats", s_print_stats) {}
else if VG_BOOL_CLO(arg, "--first-race-only", first_race_only) {}
+ else if VG_BOOL_CLO(arg, "--free-is-write", s_free_is_write) {}
else if VG_BOOL_CLO(arg,"--report-signal-unlocked",report_signal_unlocked)
{}
else if VG_BOOL_CLO(arg, "--segment-merging", segment_merging) {}
" time (in milliseconds) [off].\n"
" --first-race-only=yes|no Only report the first data race that occurs on\n"
" a memory location instead of all races [no].\n"
+" --free-is-write=yes|no Whether to report races between freeing memory\n"
+" and subsequent accesses of that memory[no].\n"
" --report-signal-unlocked=yes|no Whether to report calls to\n"
" pthread_cond_signal() where the mutex associated\n"
" with the signal via pthread_cond_wait() is not\n"
void drd_start_using_mem(const Addr a1, const SizeT len,
const Bool is_stack_mem)
{
- tl_assert(a1 <= a1 + len);
+ const Addr a2 = a1 + len;
+
+ tl_assert(a1 <= a2);
if (!is_stack_mem && s_trace_alloc)
VG_(message)(Vg_UserMsg, "Started using memory range 0x%lx + %ld%s\n",
a1, len, DRD_(running_thread_inside_pthread_create)()
? " (inside pthread_create())" : "");
+ if (!is_stack_mem && s_free_is_write)
+ DRD_(thread_stop_using_mem)(a1, a2);
+
if (UNLIKELY(DRD_(any_address_is_traced)()))
{
DRD_(trace_mem_access)(a1, len, eStart);
if (UNLIKELY(DRD_(running_thread_inside_pthread_create)()))
{
- DRD_(start_suppression)(a1, a1 + len, "pthread_create()");
+ DRD_(start_suppression)(a1, a2, "pthread_create()");
}
}
if (!is_stack_mem || DRD_(get_check_stack_accesses)())
{
- DRD_(thread_stop_using_mem)(a1, a2);
+ if (is_stack_mem || !s_free_is_write)
+ DRD_(thread_stop_using_mem)(a1, a2);
+ else if (s_free_is_write)
+ DRD_(trace_store)(a1, len);
DRD_(clientobj_stop_using_mem)(a1, a2);
DRD_(suppression_stop_using_mem)(a1, a2);
}