[RFA] Fix leak in record-full.c

Message ID 20190101133017.13425-1-philippe.waroquiers@skynet.be
State New, archived
Headers

Commit Message

Philippe Waroquiers Jan. 1, 2019, 1:30 p.m. UTC
  valgrind detects leaks in several gdb.reverse tests,
such as the below in gdb.reverse/watch-precsave.exp.

Fix the leak by rewriting the loop that frees
record_full_core_buf_list.

gdb/ChangeLog
2019-01-01  Philippe Waroquiers  <philippe.waroquiers@skynet.be>

	* record-full.c (record_full_base_target::close): Rewrite
	record_full_core_buf_list free logic.

==18847== VALGRIND_GDB_ERROR_BEGIN
==18847== 4,120 (24 direct, 4,096 indirect) bytes in 1 blocks are definitely lost in loss record 3,094 of 3,199
==18847==    at 0x4C2BE6D: malloc (vg_replace_malloc.c:309)
==18847==    by 0x405097: xmalloc (common-utils.c:44)
==18847==    by 0x5AF8EA: xnew<record_full_core_buf_entry> (poison.h:110)
==18847==    by 0x5AF8EA: record_full_core_target::xfer_partial(target_object, char const*, unsigned char*, unsigned char const*, unsigned long, unsigned long, unsigned long*) (record-full.c:2182)
==18847==    by 0x64677D: raw_memory_xfer_partial(target_ops*, unsigned char*, unsigned char const*, unsigned long, long, unsigned long*) (target.c:956)
==18847==    by 0x64691E: memory_xfer_partial_1(target_ops*, target_object, unsigned char*, unsigned char const*, unsigned long, unsigned long, unsigned long*) (target.c:1086)
---
 gdb/record-full.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)
  

Comments

Tom Tromey Jan. 1, 2019, 6:29 p.m. UTC | #1
>>>>> "Philippe" == Philippe Waroquiers <philippe.waroquiers@skynet.be> writes:

Philippe> gdb/ChangeLog
Philippe> 2019-01-01  Philippe Waroquiers  <philippe.waroquiers@skynet.be>

Philippe> 	* record-full.c (record_full_base_target::close): Rewrite
Philippe> 	record_full_core_buf_list free logic.

This is ok.  Thanks for fixing this.

Tom
  

Patch

diff --git a/gdb/record-full.c b/gdb/record-full.c
index 2b918eaabf..8738512f28 100644
--- a/gdb/record-full.c
+++ b/gdb/record-full.c
@@ -1014,15 +1014,11 @@  record_full_base_target::close ()
     }
 
   /* Release record_full_core_buf_list.  */
-  if (record_full_core_buf_list)
+  while (record_full_core_buf_list)
     {
-      for (entry = record_full_core_buf_list->prev; entry;
-	   entry = entry->prev)
-	{
-	  xfree (record_full_core_buf_list);
-	  record_full_core_buf_list = entry;
-	}
-      record_full_core_buf_list = NULL;
+      entry = record_full_core_buf_list;
+      record_full_core_buf_list = record_full_core_buf_list->prev;
+      xfree (entry);
     }
 
   if (record_full_async_inferior_event_token)