我正在尝试在Xcode中构建一个项目,但是我得到了错误Implicit declaration of function ‘clear’ is invalid in C99 Conflicting types for ‘clear’ Implicit declaration of function ‘clear’ is invalid in C99 。 这是代码: //main.c #include #include “tree.h” int main(){ clear(); // Implicit declaration of function ‘clear’ is invalid in C99 return 0; } //tree.c #include #include “tree.h” void clear(){ ///Conflicting types for ‘clear’ printf(“Command […]