Re: memory leak in read builtin

[Andreas Schwab]

Chet Ramey <chet.ramey@case.edu> writes:

> Chet Ramey wrote:
>> Andreas Schwab wrote:
>> 
>>> I can still reproduce it with 3.2.25, where the code is identical.
>> 
>> Really?  I let the loop run for 45 minutes last night before killing it,
>> without a memory allocation error.  I'll check again.
>
> And today it ran for more than an hour.  I'm not saying there isn't a
> leak; however, it doesn't appear to be very disruptive.

You are definitely not testing the same thing.

$ bash --version
GNU bash, version 3.2.25(1)-release (powerpc-suse-linux-gnu)
Copyright (C) 2005 Free Software Foundation, Inc.
$ yes | head -n100 | valgrind --leak-check=full bash -c 'while read a; do :; 
done'
==9203== Memcheck, a memory error detector.
==9203== Copyright (C) 2002-2007, and GNU GPL'd, by Julian Seward et al.
==9203== Using LibVEX rev 1732, a library for dynamic binary translation.
==9203== Copyright (C) 2004-2007, and GNU GPL'd, by OpenWorks LLP.
==9203== Using valgrind-3.2.3, a dynamic binary instrumentation framework.
==9203== Copyright (C) 2000-2007, and GNU GPL'd, by Julian Seward et al.
==9203== For more details, rerun with: -v
==9203== 
==9203== 
==9203== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 5 from 2)
==9203== malloc/free: in use at exit: 287,292 bytes in 1,092 blocks.
==9203== malloc/free: 5,765 allocs, 4,673 frees, 405,583 bytes allocated.
==9203== For counts of detected errors, rerun with: -v
==9203== searching for pointers to 1,092 not-freed blocks.
==9203== checked 150,908 bytes.
==9203== 
==9203== 200 bytes in 100 blocks are definitely lost in loss record 1 of 3
==9203==    at 0x4C6AFE0: malloc (vg_replace_malloc.c:149)
==9203==    by 0x707A0: xmalloc (xmalloc.c:87)
==9203==    by 0x69DF0: substring (stringlib.c:135)
==9203==    by 0x4CA94: string_extract_verbatim (subst.c:971)
==9203==    by 0x4CFBC: get_word_from_string (subst.c:2105)
==9203==    by 0x7B630: read_builtin (read.def:680)
==9203==    by 0x2FC50: execute_builtin (execute_cmd.c:3154)
==9203==    by 0x3110C: execute_simple_command (execute_cmd.c:3540)
==9203==    by 0x32E14: execute_command_internal (execute_cmd.c:672)
==9203==    by 0x337E8: execute_command (execute_cmd.c:352)
==9203==    by 0x33930: execute_while_or_until (execute_cmd.c:2350)
==9203==    by 0x32B74: execute_command_internal (execute_cmd.c:2318)
==9203== 
==9203== LEAK SUMMARY:
==9203==    definitely lost: 200 bytes in 100 blocks.
==9203==      possibly lost: 0 bytes in 0 blocks.
==9203==    still reachable: 287,092 bytes in 992 blocks.
==9203==         suppressed: 0 bytes in 0 blocks.
==9203== Reachable blocks (those to which a pointer was found) are not shown.
==9203== To see them, rerun with: --leak-check=full --show-reachable=yes

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
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