[so] Re: valgrind

[cosminratiu at gmail.com]

Cred ca situatia este urmatoarea: return 0 da sansa bibliotecii standard C
sa isi apeleze destructorul de la clasa string. exit(0) iese imediat, fara
sa apeleze destructorul.

E o non-problema asta pentru tine :).


On 11/1/07, Andrei Ciuca <andrei.ciuca at gmail.com> wrote:
>
> Salut, ai dreptate.
> In timp ce scoteam cod, am observat urmatoarea chestie :
> Daca rulez codul asta :
>
> int main()
> {
>
>     cout << "\n> ";
>     string line;
>     getline(cin, line);
>
>     command_t* root = NULL;
>     parse_line(line.c_str(), &root);
>
>     free_parse_memory();
>
>     exit(0);
>
> }
>
> Da outputul asta :
>
> ==2981== Memcheck, a memory error detector.
> ==2981== Copyright (C) 2002-2006, and GNU GPL'd, by Julian Seward et al.
> ==2981== Using LibVEX rev 1606, a library for dynamic binary translation.
> ==2981== Copyright (C) 2004-2006, and GNU GPL'd, by OpenWorks LLP.
> ==2981== Using valgrind-3.2.0-Debian, a dynamic binary instrumentation
> framework.
> ==2981== Copyright (C) 2000-2006, and GNU GPL'd, by Julian Seward et al.
> ==2981== For more details, rerun with: -v
> ==2981==
> ==2981== My PID = 2981, parent PID = 2259.  Prog and args are:
> ==2981==    ./tema1
> ==2981==
> --2981-- DWARF2 CFI reader: unhandled CFI instruction 0:50
> --2981-- DWARF2 CFI reader: unhandled CFI instruction 0:50
> ==2981==
> ==2981== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 17 from 1)
> ==2981== malloc/free: in use at exit: 17 bytes in 1 blocks.
> ==2981== malloc/free: 12 allocs, 11 frees, 209 bytes allocated.
> ==2981== For counts of detected errors, rerun with: -v
> ==2981== searching for pointers to 1 not-freed blocks.
> ==2981== checked 108,104 bytes.
> ==2981==
> ==2981== 17 bytes in 1 blocks are possibly lost in loss record 1 of 1
> ==2981==    at 0x401B8C7: operator new(unsigned) (vg_replace_malloc.c:163)
> ==2981==    by 0x40B0C6A: std::string::_Rep::_S_create(unsigned, unsigned,
> std::allocator<char> const&) (in /usr/lib/libstdc++.so.6.0.8)
> ==2981==    by 0x40B1BE9: std::string::_Rep::_M_clone(std::allocator<char>
> const&, unsigned) (in /usr/lib/libstdc++.so.6.0.8)
> ==2981==    by 0x40B35E7: std::string::reserve(unsigned) (in
> /usr/lib/libstdc++.so.6.0.8)
> ==2981==    by 0x4089126: std::basic_istream<char, std::char_traits<char>
> >& std::getline<char, std::char_traits<char>, std::allocator<char>
> >(std::basic_istream<char, std::char_traits<char> >&,
> std::basic_string<char, std::char_traits<char>, std::allocator<char> >&,
> char) (in /usr/lib/libstdc++.so.6.0.8)
> ==2981==    by 0x40A2178: std::basic_istream<char, std::char_traits<char>
> >& std::getline<char, std::char_traits<char>, std::allocator<char>
> >(std::basic_istream<char, std::char_traits<char> >&,
> std::basic_string<char, std::char_traits<char>, std::allocator<char> >&) (in
> /usr/lib/libstdc++.so.6.0.8)
> ==2981==    by 0x80493E9: main (tema1.cpp:875)
> ==2981==
> ==2981== LEAK SUMMARY:
> ==2981==    definitely lost: 0 bytes in 0 blocks.
> ==2981==      possibly lost: 17 bytes in 1 blocks.
> ==2981==    still reachable: 0 bytes in 0 blocks.
> ==2981==         suppressed: 0 bytes in 0 blocks.
>
>
> Daca rulez codul asta (diferenta este ca in loc sa dau "exit(0)" dau
> "return 0" ):
>
> int main()
> {
>
>     cout << "\n> ";
>     string line;
>     getline(cin, line);
>
>     command_t* root = NULL;
>     parse_line(line.c_str(), &root);
>
>     free_parse_memory();
>
>     return 0;
> }
>
> atunci valgrind spune ca totul e ok - "no memory leaks possible".
>
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