Syntax for the constructor in the template class

I am trying to create a generic circular buffer pattern, but there is some syntax error that I cannot understand. There is an error in my constructor, although it seems that I also parameterize the destructor and that it works. I followed the example in Stroustrup C ++, and it uses a parameter in front of the scope resolution operator, as well as in the function name, just like mine. I am also sure that there are no circular dependencies, because I only compile one file. In addition, the implementation and declarations are in the same file (CircBuf.h) and there is no corresponding .cpp file, so the link should not be a problem either. I tried to add the keyword "inline" according to this solution, and I get the same error.

/* CircBuf.h */
template<typename T> class CircBuf {
  // don't use default ctor                                                                                                                                               
  CircBuf();

  int size;
  T *data;
public:
  CircBuf(int);
  ~CircBuf();
};

template<typename T> CircBuff<T>::CircBuf<T>(int i) {
  data = new T[i];
}
template<typename T> CircBuf<T>::~CircBuf<T>() {
  delete data;
}

Makefile

all:
        g++ -g -pedantic CircBuf.h -o prog

CircBuf.h:13:22: error: ‘CircBuff’ does not name a type