[binutils-gdb] Fix leak of struct call_thread_fsm in call_function_by_hand_dummy.

[Philippe Waroquiers]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=e3319240732bc9543af8ced9d80ec89d0b629b2e

commit e3319240732bc9543af8ced9d80ec89d0b629b2e
Author: Philippe Waroquiers <philippe.waroquiers@skynet.be>
Date:   Tue Jan 1 20:54:52 2019 +0100

    Fix leak of struct call_thread_fsm in call_function_by_hand_dummy.
    
    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.

Diff:
---
 gdb/ChangeLog | 5 +++++
 gdb/infcall.c | 6 ++++--
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 3ec0d95..41889ba 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -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
diff --git a/gdb/infcall.c b/gdb/infcall.c
index 2a01d70..14b0cbc 100644
--- a/gdb/infcall.c
+++ b/gdb/infcall.c
@@ -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;
       }
   }