Question

我在优胜美地的Valgrind遇到了一个奇怪的问题。这是我的简单程序：

#include <stdio.h>
int main() {
    printf("Hello world %d\n", 123);
    return 0;
}

编译它然后使用Valgrind运行它我得到以下内容：

==48900== Conditional jump or move depends on uninitialised value(s)
==48900==    at 0x1003FBC3F: _platform_memchr$VARIANT$Haswell (in /usr/lib/system/libsystem_platform.dylib)
==48900==    by 0x1001EFB96: __sfvwrite (in /usr/lib/system/libsystem_c.dylib)
==48900==    by 0x1001F9FE5: __vfprintf (in /usr/lib/system/libsystem_c.dylib)
==48900==    by 0x10021F9AE: __v2printf (in /usr/lib/system/libsystem_c.dylib)
==48900==    by 0x10021FC80: __xvprintf (in /usr/lib/system/libsystem_c.dylib)
==48900==    by 0x1001F5B71: vfprintf_l (in /usr/lib/system/libsystem_c.dylib)
==48900==    by 0x1001F39D7: printf (in /usr/lib/system/libsystem_c.dylib)
==48900==    by 0x100000F51: main (test.c:3)
==48900==
Hello world 123
==48900==
==48900== HEAP SUMMARY:
==48900==     in use at exit: 39,212 bytes in 426 blocks
==48900==   total heap usage: 506 allocs, 80 frees, 45,340 bytes allocated
==48900==
==48900== LEAK SUMMARY:
==48900==    definitely lost: 16 bytes in 1 blocks
==48900==    indirectly lost: 0 bytes in 0 blocks
==48900==      possibly lost: 13,058 bytes in 117 blocks
==48900==    still reachable: 26,138 bytes in 308 blocks
==48900==         suppressed: 0 bytes in 0 blocks
==48900== Rerun with --leak-check=full to see details of leaked memory
==48900==
==48900== For counts of detected and suppressed errors, rerun with: -v
==48900== Use --track-origins=yes to see where uninitialised values come from
==48900== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 0 from 0)

有什么建议吗？

Answer 1

这很有用：Yosemite and Valgrind虽然在过去的OS X发布周期中可能出现这种情况，但Valgrind在获得合理的功能支持之前需要一段时间，但Valgrind主干已经提供了基本的OS X 10.10支持。关于预发布优胜美地的重要工作 - Dave Qorashi

未初始化的价值 - Valgrind

1 个答案: