#pragma once #include iostream #include cstring #include cstdlib #include new #include typeinfo // 可选如果不想用宏自动传名可以结合 typeid // 只在调试模式下启用 #ifdef _DEBUG struct MemHeader { char className[128]; // 存储类名 size_t size; // 用户请求的字节数 // 可以添加file, line, timestamp 等 }; // 带类名参数的 operator new inline void* operator new(size_t sz, const char* name) { size_t total sizeof(MemHeader) sz; void* raw malloc(total); if (!raw) throw std::bad_alloc(); MemHeader* h static_castMemHeader*(raw); // 安全复制类名截断超过 127 个字符 strncpy(h-className, name, sizeof(h-className) - 1); h-className[sizeof(h-className) - 1] \0; h-size sz; // 返回用户区域指针头部之后 return static_castchar*(raw) sizeof(MemHeader); } // 对应的 operator delete释放时回退头部 inline void operator delete(void* p) noexcept { if (!p) return; void* raw static_castchar*(p) - sizeof(MemHeader); free(raw); } // 为了安全也重载 placement delete如果构造函数抛出异常会调用 inline void operator delete(void* p, const char*) noexcept { ::operator delete(p); } // --- 宏定义自动传入类名--- // 用法NEW(MyClass) → 调用默认构造 // NEW(MyClass, arg1) → 调用带参构造 #define NEW(T, ...) new (#T) T(__VA_ARGS__) #else // 非调试模式直接使用标准 new #define NEW(T, ...) new T(__VA_ARGS__) #endifmain.cpp#include debug_new.h #include iostream #include unistd.h class MyClass { public: MyClass() { std::cout MyClass default constructed std::endl; } MyClass(int x) { std::cout MyClass constructed with x std::endl; } ~MyClass() { std::cout MyClass destroyed std::endl; } }; class Another { int a; public: Another(int a, double b) : a(a) { std::cout Another( a , b ) std::endl; } }; int main() { // 使用 NEW 宏自动传入类名 MyClass* obj1 NEW(MyClass); MyClass* obj2 NEW(MyClass, 42); Another* obj3 NEW(Another, 10, 3.14); while(1) sleep(1); delete obj1; delete obj2; delete obj3; return 0; }armg -D_DEBUG -g -o myapp main.cpp -stdc11Breakpoint 2, MyClass::MyClass (this0x424ca8) at main.cpp:7 7 in main.cpp (gdb) bt #0 MyClass::MyClass (this0x424ca8) at main.cpp:7 #1 0x0000000000400e4c in main () at main.cpp:20dump(gdb) p (char*)0x424ca8 - 136 $2 0x424c20 MyClass (gdb) dump memory /data/pub/d.bin 0x424ca8 0x445000 (gdb) dump memory /data/pub/d.bin 0x424ca8-136 0x445000roothovfree:/data/pub# hexdump -C d.bin 00000000 4d 79 43 6c 61 73 73 00 00 00 00 00 00 00 00 00 |MyClass.........| 00000010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| *