Why does VS require constant for array size, and MinGW does not? And is there a way around it?
I have ported some code from Mingw which i wrote using code::blocks, to visual studio and their compiler, it has picked up many errors that my array sizes must be constant! Why does VS need a constant size and mingw does not?
e.g.
const int len = (strlen(szPath)-20);
char szModiPath[len];
the len variable is underlined in red to say that its an error and says "expected constant expression"
The only 开发者_开发技巧way i can think to get around this is....
char* szModiPath = new char[len];
delete[] szModiPath;
Will i have to change everything to dynamic or is there another way in VS?
Why does VS need a constant size and mingw does not?
Because Variable Length Arrays are not a part of C++ although MinGW(g++) supports them as extension. Array size has to be a constant expression in C++.
In C++ it is always recommended to use std::vector
instead of C-style arrays
. :)
The only way i can think to get around this is....
This is not "the only way". Use STL containers.
#include <string>
....
std::string s;
s.resize(len);
or
#include <vector>
....
std::vector<char> buffer(len);
P.S. Also, I don't think that using hungarian notation in C++ code is a good idea.
Use _alloca to allocate variable amounts off the stack, then write an encapsulating class. It's a litlte messy, but you CAN write your own variable length stack-based arrays.
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