🚀 go-pugleaf

/*****
 *****
 **
 **     This code demonstrates cpp behaviour that I would like to see
 **     cpp emit a warning message for.  When a #define over-rides an
 **     enum, I would like cpp to warn me about what is taking place.
 **     This should only be enabled by specific user request, or by
 **     ``gcc -Wall''.  
 **
 **     This code appears to compile alright, but it will never
 **     execute as I had intended (because the enum's value is 0 and
 **     the #define's value is 1).  Unfortunately, this problem is
 **     hard to find when it is one of the system header files that is
 **     over-riding an enum in my own code.
 **
 *****
 *****/

typedef enum {
    OK,
    NOTOK
    } okType;

#define OK      (1)

okType main() {
    okType imok = OK;

    /* lots of code that may conditionally set imok to NOTOK */
    
    if (imok == NOTOK) {
        printf("Premature return\n.");
        return imok;
    } else {
        printf("Returned properly\n.");
    }

    return imok;
}

/***** Here's what ``gcc -E'' emits for this code (with empty lines removed): *****

#1 "hassle.c"

typedef enum { 
OK , 
NOTOK 
} okType ; 

okType main ( ) 
{ 
okType imok = ( 1 ) ; 

if ( imok == NOTOK ) { 
printf ( "Premature return\n." ) ; 
return imok ; 
} else { 
printf ( "Returned properly\n." ) ; 
} 

return imok ; 
} 

***** end of ``gcc -E'' output *****/

--
 === Christopher Rath ===== crath@bnr.ca ===== (613) 765-3141 ===
  Bell-Northern Research |
  Box 3511, Station `C'  | ``Hydrogen is a colourless, odourless
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