/* h1.h */ #ifndef H1_H #define H1_H ... #ifndef COUNT_T #define COUNT_T typedef unsigned int count; #endif ... #endif /* h2.h */ #ifndef H2_H #define H2_H ... #ifndef COUNT_T #define COUNT_T typedef unsigned int count; #endif ... #endif #include "h1.h" /* count defined */ #include "h2.h" /* count not redefined */