1f1f4bc21SRichard Smith typedef union {} pthread_mutex_t; 2*c0ca4c2cSRichard Smith 3*c0ca4c2cSRichard Smith // Define then merge with another definition. 4*c0ca4c2cSRichard Smith typedef struct {} merged_after_definition; 5*c0ca4c2cSRichard Smith #include "c1.h" 6