成员函数指针做回调参数总结 踩坑
一、程序升级后,在linux上编译提示错误:
warning: converting from ‘int (MyClass::)()’ to ‘void ()()’ [-Wpmf-conversions]
void(myStoredFunction)(void) = (GENERIC_FUNC_TYPE)memberFunc; // Compiler warning
二、出现这个情况是因为,程序的这个模块是早期开发的,使用的是gcc4开发的,现在升级到gcc7,c++版本兼容性问题,具体解决方法如下:
1:用内联汇编方式,跳过c++,语法检测,x86_64汇编代码如下:
asm (
"mov %1, %0"
:"=r"(addr)
:"r"(&TEST::foo)
);
或者这样更好:
asm ( "" // no instructions
:"=r"(addr)
:"0"(&TEST::foo) // same register as operand 0
);
2:c++语法转换方式,代码如下:
template <typename C, void (C::M)()>
void* AsFunc(void* p)
{
(static_cast<C>(p)->M)();
}
调用:void (myExtractedFunction)(void) = &AsFunc<MyClass, &MyClass::myMemberFunc>;
或者:
template<typename dst_type,typename src_type>
dst_type pointer_cast(src_type src)
{
return static_cast<dst_type>(static_cast<void*>(&src));
}
三、区别总结
参考相关文献
成员函数指针
C++函数指针、函数对象与C++11 function对象对比分析
C++ 强制类型转换操作符static_cast
C++ 动态联编实现原理分析
C++类成员函数调用分析
Pointers to Member Functions
a pointer to member function to be invoked by the target class without functional
Declares a variable of a pointer or pointer-to-member type.
标签:void,C++,cast,参数,static,函数指针,回调,pointer
From: https://www.cnblogs.com/shuigsls/p/17902391.html