2010-05-19 56 views
11

當我使用valgrind來幫助調試我正在處理的應用程序時,我注意到很多噪聲似乎在抱怨標準庫。作爲一個測試,我做了這個;Valgrind'噪音',這是什麼意思?

echo 'int main() {return 0;}' | gcc -x c -o test - 

然後我做到了這一點;

valgrind ./test 

==1096== Use of uninitialised value of size 8 
==1096== at 0x400A202: _dl_new_object (in /lib64/ld-2.10.1.so) 
==1096== by 0x400607F: _dl_map_object_from_fd (in /lib64/ld-2.10.1.so) 
==1096== by 0x4007A2C: _dl_map_object (in /lib64/ld-2.10.1.so) 
==1096== by 0x400199A: map_doit (in /lib64/ld-2.10.1.so) 
==1096== by 0x400D495: _dl_catch_error (in /lib64/ld-2.10.1.so) 
==1096== by 0x400189E: do_preload (in /lib64/ld-2.10.1.so) 
==1096== by 0x4003CCD: dl_main (in /lib64/ld-2.10.1.so) 
==1096== by 0x401404B: _dl_sysdep_start (in /lib64/ld-2.10.1.so) 
==1096== by 0x4001471: _dl_start (in /lib64/ld-2.10.1.so) 
==1096== by 0x4000BA7: (within /lib64/ld-2.10.1.so) 
* large block of similar snipped * 
==1096== Use of uninitialised value of size 8 
==1096== at 0x4F35FDD: (within /lib64/libc-2.10.1.so) 
==1096== by 0x4F35B11: (within /lib64/libc-2.10.1.so) 
==1096== by 0x4A1E61C: _vgnU_freeres (vg_preloaded.c:60) 
==1096== by 0x4E5F2E4: __run_exit_handlers (in /lib64/libc-2.10.1.so) 
==1096== by 0x4E5F354: exit (in /lib64/libc-2.10.1.so) 
==1096== by 0x4E48A2C: (below main) (in /lib64/libc-2.10.1.so) 
==1096== 
==1096== ERROR SUMMARY: 3819 errors from 298 contexts (suppressed: 876 from 4) 
==1096== malloc/free: in use at exit: 0 bytes in 0 blocks. 
==1096== malloc/free: 0 allocs, 0 frees, 0 bytes allocated. 
==1096== For counts of detected errors, rerun with: -v 
==1096== Use --track-origins=yes to see where uninitialised values come from 
==1096== All heap blocks were freed -- no leaks are possible. 

你可以看到完整的結果在這裏: http://pastebin.com/gcTN8xGp

我有兩個問題;首先有辦法抑制所有的噪音?

--show-below-main在默認情況下設置爲no,但似乎沒有顯示爲 - show-main-after-main等效。

回答

5

升級到Valgrind 3.5.0或更高版本。除其他外,默認的.supp文件已被更新。

12

您可以通過附加

{ 
    ld error suppression 
    Memcheck:Cond 
    fun:dl_main 
    fun:_dl_sysdep_start 
    fun:_dl_start 
    obj:/lib64/ld-2.10.1.so 
} 

/usr/lib/valgrind/default.supp(或定義自己的抑制文件)抑制輸出。

它似乎是一個已知的鏈接器/加載程序錯誤,至少Debian & Arch Linux開發人員;我對其餘部分以及他們計劃的行動方案不確定。

+0

這個問題是使用比Valgrind熟悉的更新的glibc。 +1指向正確的方向。 – 2010-05-19 14:27:00

4

我不時有這些症狀,並且解決方案總是讓升級我的valgrind和libc軟件包以便同步。 Debian的精靈小精靈負責其餘部分。