Qt C++ does not see the standard C++libraries

I write a program in Qt. And when you add modules to it, the following comes out. Let's say everyone knows string.h, the c++standard library. It definitely has strcmp in it. If I work with strcmp in visual studio without adding anything, this does not cause any problems, because vs finds strcmp in string h. And in qt writes "no matching function for call" strcmp" so is c compare. Question why does qt not want to see the standard values of c++libraries

Author: Артем Райзенов, 2020-12-31