n_1:    Trigraph sequences.             

n_2:    Line splicing by <backslash>.   

n_3:    Handling of comment.            

n_4:    Tokens spelled by digraphs.     

n_5:    Spaces or tabs in pp-directive. 

n_6:    #include directive.             

n_7:    #line directive.                

n_9:    #pragma directive.              

n_10:   #if, #elif pp-directive.        

n_11:   Operator "defined" in #if.      

n_12:   Pp-number and type of #if expr. 

n_13:   Valid operators in #if expr.    

n_13.5: Usual arithmetic conversion.    

n_13.7: Short-circuit evaluation of #if.

n_13.8: Grouping of #if sub-expressions.

n_13.13:    #if expression with macros. 

n_15:   #ifdef, #ifndef directives.     

n_18:   #define directive.              

n_19:   Valid re-definitions of macros. 

n_20:   Macro name identical to keyword.

n_21:   Tokenization (no token merging).

n_22:   Tokenization of pp-number.      

n_23:   ## operator in macro definition.

n_24:   # operator in macro definition. 

n_25:   Pre-expansion of macro args.    

n_26:   No recursive replacement.       

n_27:   Rescanning of a macro.          

n_28:   Standard pre-defined macros.    

n_29:   #undef directive.               

n_30:   Macro call crossing lines.      

n_32:   Escape sequence in char-const.  

n_37:   Translation limits.             

i_32.3: Character constant in #if.      

i_35:   Multi-character character const.

i_35.3: Multi-character wide character. 

Total number of tests unpassed.