Microchip Technology XC8 Standard Compiler (Workstation) SW006021-1 SW006021-1 ユーザーズマニュアル

 2012 Microchip Technology Inc.

DS52053B-page 385

A macro has been invoked with the wrong number of arguments, for example:

#define ADD(a, b) (a+b)

ADD(1, 2, 3)        /* oops -- only two arguments required */

The stringization operator # (not to be confused with the leading # used for preproces-
sor control lines) must be followed by a formal macro parameter, for example:

#define str(x) #y  /* oops -- did you mean x instead of y? */

If you need to stringize a token, you will need to define a special macro to do it, for 
example:

#define __mkstr__(x) #x

then use __mkstr__(token) wherever you need to convert a token into a string.

A symbol on a #if expression was not a defined preprocessor macro. For the pur-
poses of this expression, its value has been taken as zero. This warning may be dis-
abled with some compilers. Example:

#if FOO+BAR    /* e.g. FOO was never #defined */

  #define GOOD

#endif

Multi-byte constants are not portable, and in fact will be rejected by later passes of the 
compiler, for example:

#if CHAR == ’ab’

  #define MULTI

#endif

Inside a #if expression, there is a division by zero which has been treated as yielding 
zero, for example:

#if foo/0  /* divide by 0: was this what you were intending? */

  int a;

#endif

A new line is missing at the end of the line. Each line, including the last line, must have 
a new line at the end. This problem is normally introduced by editors.

A macro name specified in a -U option to the preprocessor was not initially defined, and 
thus cannot be undefined.

This warning is issued when nested comments are found. A nested comment may indi-
cate that a previous closing comment marker is missing or malformed, for example:

output = 0;  /* a comment that was left unterminated

flag = TRUE; /* next comment:

                hey, where did this line go? */