Re: Crash regression for gdb.base/ending-run.exp [Re: creating the gdb-7.4 branch tomorrow (?)]

Tom Tromey
2011-12-09T18:40:24Z

>>>>> "Jan" == Jan Kratochvil <jan.kratochvil@redhat.com> writes:

Jan> Regression on Fedoras, such as F-15 x86_64 using .debug_types:

Jan> DEJAGNU=$HOME/src/runtest-valgrind/site.exp runtest CC_FOR_TARGET="gcc -gdwarf-4 -fdebug-types-section -g0" CXX_FOR_TARGET="g++ -gdwarf-4 -fdebug-types-section -g0" --target_board valgrind gdb.base/ending-run.exp

Thanks.

I'm checking in the appended.

The bug was that a given breakpoint could end up on the 'found' list
more than once. My fix is to remove duplicates from the list.

Also I noticed that the VEC created in clear_command was never freed.
This patch fixes that as well.

Built and regtested on x86-64 F15. I also ran the test above before and
after the patch.

Tom

2011-12-09 Tom Tromey <tromey@redhat.com>

* breakpoint.c (compare_breakpoints): New function.
(clear_command): Remove duplicate breakpoints. Properly clean
up.

diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index d9d5bbe..6f4f2d6 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -10028,18 +10028,41 @@ tcatch_command (char *arg, int from_tty)
error (_("Catch requires an event name."));
}

+/* A qsort comparison function that sorts breakpoints in order. */
+
+static int
+compare_breakpoints (const void *a, const void *b)
+{
+ const breakpoint_p *ba = a;
+ uintptr_t ua = (uintptr_t) *ba;
+ const breakpoint_p *bb = b;
+ uintptr_t ub = (uintptr_t) *bb;
+
+ if ((*ba)->number < (*bb)->number)
+ return -1;
+ else if ((*ba)->number > (*bb)->number)
+ return 1;
+
+ /* Now sort by address, in case we see, e..g, two breakpoints with
+ the number 0. */
+ if (ua < ub)
+ return -1;
+ return ub > ub ? 1 : 0;
+}
+
/* Delete breakpoints by address or line. */

static void
clear_command (char *arg, int from_tty)
{
- struct breakpoint *b;
+ struct breakpoint *b, *prev;
VEC(breakpoint_p) *found = 0;
int ix;
int default_match;
struct symtabs_and_lines sals;
struct symtab_and_line sal;
int i;
+ struct cleanup *cleanups = make_cleanup (null_cleanup, NULL);

if (arg)
{
@@ -10090,6 +10113,7 @@ clear_command (char *arg, int from_tty)
breakpoint. */

found = NULL;
+ make_cleanup (VEC_cleanup (breakpoint_p), &found);
for (i = 0; i < sals.nelts; i++)
{
/* If exact pc given, clear bpts at that pc.
@@ -10143,6 +10167,7 @@ clear_command (char *arg, int from_tty)
VEC_safe_push(breakpoint_p, found, b);
}
}
+
/* Now go thru the 'found' chain and delete them. */
if (VEC_empty(breakpoint_p, found))
{
@@ -10152,6 +10177,21 @@ clear_command (char *arg, int from_tty)
error (_("No breakpoint at this line."));
}

+ /* Remove duplicates from the vec. */
+ qsort (VEC_address (breakpoint_p, found),
+ VEC_length (breakpoint_p, found),
+ sizeof (breakpoint_p),
+ compare_breakpoints);
+ prev = VEC_index (breakpoint_p, found, 0);
+ for (ix = 1; VEC_iterate (breakpoint_p, found, ix, b); ++ix)
+ {
+ if (b == prev)
+ {
+ VEC_ordered_remove (breakpoint_p, found, ix);
+ --ix;
+ }
+ }
+
if (VEC_length(breakpoint_p, found) > 1)
from_tty = 1; /* Always report if deleted more than one. */
if (from_tty)
@@ -10171,6 +10211,8 @@ clear_command (char *arg, int from_tty)
}
if (from_tty)
putchar_unfiltered ('\n');
+
+ do_cleanups (cleanups);
}
\f
/* Delete breakpoint in BS if they are `delete' breakpoints and