Question

我全局替换了new / delete以确保我的对象正确对齐以进行快速计算：

#ifdef __WAND__
target[name[new.o] type[object] platform[;GNU/Linux]]
#endif

#include <cstddef>
#include <stdlib.h>

#include <cstdio>

void* operator new(size_t count)
    {
    void* buffer;
    int res=posix_memalign(&buffer,64,count);
    if(res==0)
        {
        printf("Allocated %zu bytes at %p\n",count,buffer);
        return buffer;
        }
    return NULL;
    }

void operator delete(void* buffer)
    {
    printf("Free buffer %p\n",buffer);
    free(buffer);
    }

void* operator new[](size_t count)
    {
    void* buffer;
    int res=posix_memalign(&buffer,64,count);
    if(res==0)
        {
        printf("Allocated %zu bytes at %p\n",count,buffer);
        return buffer;
        }
    return NULL;
    }

void operator delete[](void* buffer)
    {
    printf("Free buffer %p\n",buffer);
    free(buffer);
    }

在stdout获得比预期更多的内容后，我检查了谁调用了我的new运算符。这是回溯的样子：

#0  operator new (count=4) at new.cpp:13
#1  0xb753a87d in ?? () from /usr/lib/i386-linux-gnu/dri/i915_dri.so
#2  0xb7420e96 in ?? () from /usr/lib/i386-linux-gnu/dri/i915_dri.so
#3  0xb7420f31 in ?? () from /usr/lib/i386-linux-gnu/dri/i915_dri.so
#4  0xb73cb710 in ?? () from /usr/lib/i386-linux-gnu/dri/i915_dri.so
#5  0xb7422dc5 in ?? () from /usr/lib/i386-linux-gnu/dri/i915_dri.so
#6  0xb7422ec4 in ?? () from /usr/lib/i386-linux-gnu/dri/i915_dri.so
#7  0xb7467da0 in ?? () from /usr/lib/i386-linux-gnu/dri/i915_dri.so
#8  0xb7ed02cc in fgDisplayMenu () from /usr/lib/i386-linux-gnu/libglut.so.3
#9  0xb7eced1c in ?? () from /usr/lib/i386-linux-gnu/libglut.so.3
#10 0xb7ed285f in fgEnumWindows () from /usr/lib/i386-linux-gnu/libglut.so.3
#11 0xb7ecf26e in glutMainLoopEvent () from /usr/lib/i386-linux-gnu/libglut.so.3
#12 0xb7ecfabc in glutMainLoop () from /usr/lib/i386-linux-gnu/libglut.so.3
#13 0x0804acaf in GlutWindow::mainLoopRun () at glutwindow.cpp:28
#14 0x080496db in main (argc=1, argv=0xbfffeb34) at main.cpp:28

那么为什么低级图形库会调用我的new运算符？是否有任何其他原因（一些黑魔法）比用C ++编写的这个库（我认为大多数这样的东西是用C或汇编编写的）使用new / delete而不是malloc / free？

Answer 1

低级库可能部分或完全写入C++。没有其他原因（黑魔法）来调用新的操作符。

替换operator new和delete似乎影响C库

1 个答案: