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valgrind ソースコードを使って実験をしようとしています。テストコードとして以下のコードを使用しています。

#include <stdio.h>
int g_int = 12;
int main()
{
  int y = 10;
  int x;
  printf("%d\n",x);
  return x;
}

「test.out」という名前の実行可能ファイルをビルドします。次に、以下のコマンドを実行しました。

$./valgrind --tool=memcheck ./test.out

私のテスト コードには初期化されていないバグがあり、valgrind は " mc_errors.c " からのバグを次のようなメッセージで報告します。

../build/bin$ ./valgrind --tool=memcheck --track-origins=yes --read-var-info=yes ./test >> outpur.txt
==24255== Memcheck, a memory error detector
==24255== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==24255== Using Valgrind-3.14.0.GIT and LibVEX; rerun with -h for copyright info
==24255== Command: ./test
==24255== 
==24255== Conditional jump or move depends on uninitialised value(s)
==24255== I want to print my local variable here!
==24255==    at 0x4E87B83: vfprintf (vfprintf.c:1631)
==24255==    by 0x4E8F898: printf (printf.c:33)
==24255==    by 0x400548: main (test.c:10)
==24255==  Uninitialised value was created by a stack allocation
==24255==    at 0x400526: main (test.c:6)
==24255== 
==24255== Use of uninitialised value of size 8
==24255== I want to print my local variable here!
==24255==    at 0x4E8476B: _itoa_word (_itoa.c:179)
==24255==    by 0x4E8812C: vfprintf (vfprintf.c:1631)
==24255==    by 0x4E8F898: printf (printf.c:33)
==24255==    by 0x400548: main (test.c:10)
==24255==  Uninitialised value was created by a stack allocation
==24255==    at 0x400526: main (test.c:6)
==24255== 
==24255== Conditional jump or move depends on uninitialised value(s)
==24255== I want to print my local variable here!
==24255==    at 0x4E84775: _itoa_word (_itoa.c:179)
==24255==    by 0x4E8812C: vfprintf (vfprintf.c:1631)
==24255==    by 0x4E8F898: printf (printf.c:33)
==24255==    by 0x400548: main (test.c:10)
==24255==  Uninitialised value was created by a stack allocation
==24255==    at 0x400526: main (test.c:6)
==24255== 
==24255== Conditional jump or move depends on uninitialised value(s)
==24255== I want to print my local variable here!
==24255==    at 0x4E881AF: vfprintf (vfprintf.c:1631)
==24255==    by 0x4E8F898: printf (printf.c:33)
==24255==    by 0x400548: main (test.c:10)
==24255==  Uninitialised value was created by a stack allocation
==24255==    at 0x400526: main (test.c:6)
==24255== 
==24255== Conditional jump or move depends on uninitialised value(s)
==24255== I want to print my local variable here!
==24255==    at 0x4E87C59: vfprintf (vfprintf.c:1631)
==24255==    by 0x4E8F898: printf (printf.c:33)
==24255==    by 0x400548: main (test.c:10)
==24255==  Uninitialised value was created by a stack allocation
==24255==    at 0x400526: main (test.c:6)
==24255== 
==24255== Conditional jump or move depends on uninitialised value(s)
==24255== I want to print my local variable here!
==24255==    at 0x4E8841A: vfprintf (vfprintf.c:1631)
==24255==    by 0x4E8F898: printf (printf.c:33)
==24255==    by 0x400548: main (test.c:10)
==24255==  Uninitialised value was created by a stack allocation
==24255==    at 0x400526: main (test.c:6)
==24255== 
==24255== Conditional jump or move depends on uninitialised value(s)
==24255== I want to print my local variable here!
==24255==    at 0x4E87CAB: vfprintf (vfprintf.c:1631)
==24255==    by 0x4E8F898: printf (printf.c:33)
==24255==    by 0x400548: main (test.c:10)
==24255==  Uninitialised value was created by a stack allocation
==24255==    at 0x400526: main (test.c:6)
==24255== 
==24255== Conditional jump or move depends on uninitialised value(s)
==24255== I want to print my local variable here!
==24255==    at 0x4E87CE2: vfprintf (vfprintf.c:1631)
==24255==    by 0x4E8F898: printf (printf.c:33)
==24255==    by 0x400548: main (test.c:10)
==24255==  Uninitialised value was created by a stack allocation
==24255==    at 0x400526: main (test.c:6)
==24255== 
==24255== 
==24255== HEAP SUMMARY:
==24255==     in use at exit: 0 bytes in 0 blocks
==24255==   total heap usage: 1 allocs, 1 frees, 4,096 bytes allocated
==24255== 
==24255== All heap blocks were freed -- no leaks are possible
==24255== 
==24255== For counts of detected and suppressed errors, rerun with: -v
==24255== ERROR SUMMARY: 8 errors from 8 contexts (suppressed: 0 from 0)

ここで、「 g_int」と「y」の値を valgrind からのメッセージ (バグ レポート) と共に出力したいと考えています。私はすでに valgrind ソース印刷に印刷を追加しています:「ローカル変数をここに印刷したい!」内部APIを使用してvalgrindソースからユーザーソースコードから変数の値を読み取る方法はありますか? ユーザーコードからすべての変数名を取得できれば、プラスになります。

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3 に答える 3

2

VALGRIND_COUNT_ERRORSこれには、VALGRIND_PRINTFValgrind Client Requestsを使用できます。

サンプルコードでそれらを使用する方法は次のとおりです。

#include <stdio.h>
#include <valgrind/valgrind.h>

int g_int = 12;
int main()
{
  int y = 10;
  int x;
  printf("%d\n",x);
  if (VALGRIND_COUNT_ERRORS > 0)
  {
    VALGRIND_PRINTF("y=%d, g_int=%d\n", y, g_int);
  }
  return x;
}

Valgrind 出力:

==4030== Memcheck, a memory error detector
==4030== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==4030== Using Valgrind-3.13.0 and LibVEX; rerun with -h for copyright info
==4030== Command: ./a.out
==4030== 
==4030== Conditional jump or move depends on uninitialised value(s)
==4030==    at 0x4E90DDA: vfprintf (in /usr/lib64/libc-2.26.so)
==4030==    by 0x4E99285: printf (in /usr/lib64/libc-2.26.so)
==4030==    by 0x400719: main (in /home/ks/a.out)
==4030== 
==4030== Use of uninitialised value of size 8
==4030==    at 0x4E8CDAB: _itoa_word (in /usr/lib64/libc-2.26.so)
==4030==    by 0x4E9046D: vfprintf (in /usr/lib64/libc-2.26.so)
==4030==    by 0x4E99285: printf (in /usr/lib64/libc-2.26.so)
==4030==    by 0x400719: main (in /home/ks/a.out)
==4030== 
==4030== Conditional jump or move depends on uninitialised value(s)
==4030==    at 0x4E8CDB5: _itoa_word (in /usr/lib64/libc-2.26.so)
==4030==    by 0x4E9046D: vfprintf (in /usr/lib64/libc-2.26.so)
==4030==    by 0x4E99285: printf (in /usr/lib64/libc-2.26.so)
==4030==    by 0x400719: main (in /home/ks/a.out)
==4030== 
==4030== Conditional jump or move depends on uninitialised value(s)
==4030==    at 0x4E90572: vfprintf (in /usr/lib64/libc-2.26.so)
==4030==    by 0x4E99285: printf (in /usr/lib64/libc-2.26.so)
==4030==    by 0x400719: main (in /home/ks/a.out)
==4030== 
==4030== Conditional jump or move depends on uninitialised value(s)
==4030==    at 0x4E9104C: vfprintf (in /usr/lib64/libc-2.26.so)
==4030==    by 0x4E99285: printf (in /usr/lib64/libc-2.26.so)
==4030==    by 0x400719: main (in /home/ks/a.out)
==4030== 
0
**4030** y=10, g_int=12
==4030== Syscall param exit_group(status) contains uninitialised byte(s)
==4030==    at 0x4F1A478: _Exit (in /usr/lib64/libc-2.26.so)
==4030==    by 0x4E77B3A: __run_exit_handlers (in /usr/lib64/libc-2.26.so)
==4030==    by 0x4E77BD9: exit (in /usr/lib64/libc-2.26.so)
==4030==    by 0x4E5D040: (below main) (in /usr/lib64/libc-2.26.so)
==4030== 
==4030== 
==4030== HEAP SUMMARY:
==4030==     in use at exit: 0 bytes in 0 blocks
==4030==   total heap usage: 1 allocs, 1 frees, 1,024 bytes allocated
==4030== 
==4030== All heap blocks were freed -- no leaks are possible
==4030== 
==4030== For counts of detected and suppressed errors, rerun with: -v
==4030== Use --track-origins=yes to see where uninitialised values come from
==4030== ERROR SUMMARY: 6 errors from 6 contexts (suppressed: 0 from 0)

変数g_intyは、次の行に出力されます。

**4030** y=10, g_int=12
于 2017-11-27T20:03:28.830 に答える