[Elftoolchain-developers] Memory leaks in libdwarf

[邓尧 <to...@gm...>]

Hi,
I just wrote a simple "hello world" program with libdwarf. It just create a
Dwarf_Debug instance and then destroy it, simple as this, I still got
memory leaks.

elftoolchain built with command "pmake MKPIC=yes MKPROFILE=no MKLINKLIB=no
-k", the platform is Ubuntu Linux 12.04, gcc 4.7, x86_64, kernel version
3.2.0.
I tried both elftoolchain-0.6.1 and the latest svn trunk. got similar leak
information from valgrind, here is my source code (linked against
libelf_pic.a & libdwarf_pic.a)

#include <unistd.h>
#include <fcntl.h>
#include <dwarf.h>
#include <libdwarf.h>
#include <assert.h>

int main() {
    Dwarf_Debug debug;
    Dwarf_Error error;
    int descriptor = open("a.out", O_RDONLY); // "a.out" is the program
itself.
    assert(dwarf_init(descriptor, DW_DLC_READ, NULL, NULL, &debug, &error)
== 0);
    dwarf_finish(debug, &error);
    close(descriptor);
    return 0;
}

This is the leak information reported by valgrind:

==1909== Memcheck, a memory error detector
==1909== Copyright (C) 2002-2011, and GNU GPL'd, by Julian Seward et al.
==1909== Using Valgrind-3.7.0 and LibVEX; rerun with -h for copyright info
==1909== Command: ./a.out
==1909==
==1909==
==1909== HEAP SUMMARY:
==1909==     in use at exit: 29,763 bytes in 57 blocks
==1909==   total heap usage: 63 allocs, 6 frees, 31,307 bytes allocated
==1909==
==1909== 29,763 (136 direct, 29,627 indirect) bytes in 1 blocks are
definitely lost in loss record 9 of 9
==1909==    at 0x4C2B6CD: malloc (in
/usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==1909==    by 0x41EFFA: _libelf_allocate_elf (in /tmp/a.out)
==1909==    by 0x4138F6: _libelf_memory (in /tmp/a.out)
==1909==    by 0x411EBE: _libelf_open_object (in /tmp/a.out)
==1909==    by 0x410CFB: elf_begin (in /tmp/a.out)
==1909==    by 0x4014A7: dwarf_init (in /tmp/a.out)
==1909==    by 0x401187: main (dw.c:11)
==1909==
==1909== LEAK SUMMARY:
==1909==    definitely lost: 136 bytes in 1 blocks
==1909==    indirectly lost: 29,627 bytes in 56 blocks
==1909==      possibly lost: 0 bytes in 0 blocks
==1909==    still reachable: 0 bytes in 0 blocks
==1909==         suppressed: 0 bytes in 0 blocks
==1909==
==1909== For counts of detected and suppressed errors, rerun with: -v
==1909== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 2 from 2)

Thanks
Yao