Fix leak of struct call_thread_fsm in call_function_by_hand_dummy.
authorPhilippe Waroquiers <philippe.waroquiers@skynet.be>
Tue, 1 Jan 2019 19:54:52 +0000 (20:54 +0100)
committerPhilippe Waroquiers <philippe.waroquiers@skynet.be>
Wed, 2 Jan 2019 21:10:39 +0000 (22:10 +0100)
When the call does not complete, the call_thread_fsm allocated
by new_call_thread_fsm is not cleaned up and deleted, which causes
the following leak e.g. in gdb.base/callfuncs.exp:

==29263== 560 bytes in 7 blocks are definitely lost in loss record 2,833 of 3,341
==29263==    at 0x4C2E0BC: calloc (vg_replace_malloc.c:762)
==29263==    by 0x405110: xcalloc (common-utils.c:84)
==29263==    by 0x4E67EB: xcnew<call_thread_fsm> (poison.h:122)
==29263==    by 0x4E67EB: new_call_thread_fsm (infcall.c:516)
==29263==    by 0x4E67EB: call_function_by_hand_dummy(value*, type*, gdb::array_view<value*>, void (*)(void*, int), void*) (infcall.c:1154)
==29263==    by 0x4E784E: call_function_by_hand(value*, type*, gdb::array_view<value*>) (infcall.c:693)
==29263==    by 0x496111: eval_call(expression*, noside, int, value**, char const*, type*) [clone .isra.5] (eval.c:835)

Fix the leak by similarly doing cleanup/destroy when restoring
previous state machine.

Tested on debian/amd64, natively and under valgrind.

2019-01-02  Philippe Waroquiers  <philippe.waroquiers@skynet.be>

* infcall.c (call_function_by_hand_dummy): cleanup/destroy sm
 in case of call that did not complete.

gdb/ChangeLog
gdb/infcall.c

index 3ec0d95..41889ba 100644 (file)
@@ -1,3 +1,8 @@
+2019-01-02  Philippe Waroquiers  <philippe.waroquiers@skynet.be>
+
+       * infcall.c (call_function_by_hand_dummy): cleanup/destroy sm
+        in case of call that did not complete.
+
 2019-01-02  Andrey Utkin  <autkin@undo.io>
 
        * symfile.c (find_separate_debug_file): Fix search of debug files for
index 2a01d70..14b0cbc 100644 (file)
@@ -1189,8 +1189,10 @@ call_function_by_hand_dummy (struct value *function,
            return retval;
          }
 
-       /* Didn't complete.  Restore previous state machine, and
-          handle the error.  */
+       /* Didn't complete.  Clean up / destroy the call FSM, and restore the
+          previous state machine, and handle the error.  */
+       thread_fsm_clean_up (call_thread->thread_fsm, call_thread.get ());
+       thread_fsm_delete (call_thread->thread_fsm);
        call_thread->thread_fsm = saved_sm;
       }
   }