Conversions between character pointers

[Spiros Bousbouras]

int foo(void) {
char c = 0 , *p = &c ;
unsigned char *up = (unsigned char)p ;
signed char *sp = (signed char)up ;

return p == (char)up && p == (char)sp &&
up == (unsigned char)sp &&
sp == (signed char)p ;
}

Is foo() guaranteed to always return 1 ? Based on 6.2.5 p26 and 6.3.2.3
p7 I would say yes.

 

[Ben Bacarisse]

int foo(void) {
char c = 0 , *p = &c ;
unsigned char *up = (unsigned char)p ;
signed char *sp = (signed char)up ;

return p == (char)up && p == (char)sp &&
up == (unsigned char)sp &&
sp == (signed char)p ;
}

Is foo() guaranteed to always return 1 ? Based on 6.2.5 p26 and 6.3.2.3
p7 I would say yes.

Not without six *s being added in the right places!

 

[Spiros Bousbouras]

Not without six *s being added in the right places!

Sorry , here's correct code :

int foo(void) {
char c = 0 , *p = &c ;
unsigned char *up = (unsigned char *)p ;
signed char *sp = (signed char *)up ;

return p == (char *)up && p == (char *)sp &&
up == (unsigned char *)sp &&
sp == (signed char *)p ;
}