As follows, custom macros in encounters an error, prompt parameter number is not enough, and in fact if a macro nested correctly, number of parameters should be enough
Main. C: 51:46: error: macro "my_print requires 5" the arguments, but only 2 given
Voss_print (COMM_INFO, "test print \ n");

 # define SUBSYS_NO 1 
# define MDLNO_COMM 1 
# define PRINT_INFO 1 

# define COMM_INFO SUBSYS_NO MDLNO_COMM, PRINT_INFO 

# define the_print printf 
# define my_print (subsystem, module, level, format,... ) the_print (format, # # __VA_ARGS__) 


My_print (1, 1, 1, "test print \ n"); 
My_print (1, 1, 1, "test print % d \ n", 1); 
/* this a compiler error, macro expansion after the compiler thinks parameter number not enough */
My_print (COMM_INFO, "test print \ n"); 

CodePudding user response:

You are using the macro function is nested inside the macro rare writing you can directly precompiled in C and see what is a
This code error occurs at compile time rather than pretreatment period under Linux easily by GCC view pretreatment may be inconsistent and you want,

CodePudding user response:

 
Int main () 
{









Printf (" test print \ n "); 
Printf (" test print \ n "); 

The printf (); 
return 0; 
} 

After preprocessing. I file code is empty after you macro substitution

CodePudding user response:

 # define COMM_INFO SUBSYS_NO MDLNO_COMM, PRINT_INFO 

The macro definition has a problem, it is suggested that see COMM_INFO content, COMM_INFO corresponding SUBSYS_NO