HP aC++/HP C A.06.20 Programmer's Guide

This option causes return types of unprototyped functions to be treated as long, instead
of int, matching Tru64 C behavior. This can prevent segfaults in +DD64 mode, resulting
from pointer truncation, for instance:
long *a;
long sub() {
a = malloc(sizeof(long)); /* no prototype! */
*a = 1234; /* segfault if +DD64 and no +tru64 */
return *a;
}
A preferable solution is to provide the appropriate function prototypes.
NOTE: This option is applicable to C language only.
-Wc,-ansi_for_scope,[on|off]
-Wc,-ansi_for_scope,[on|off]
The -Wc,-ansi_for_scope is option enables or disables the standard scoping rules
for init declarations in for statements; the scope of the declaration then ends with the
scope of the loop body. By default, the option is disabled.
Examples:
In the following example, if the option is not enabled (the current default), the scope
of k extends to the end of the body of main and statement (1) is valid (and will return
zero). With the option enabled, k is no longer in scope and (1) is an error.
#include <stdio.h>
int main() {
for (int k = 0; k!=100; ++k) {
printf(“%d\n”, k);
}
return 100-k; // (1)
}
In the next example, with the option disabled, the code is illegal, because it redefines
k in (2) when a previous definition (1) is considered to have occurred in the same scope.
With the option enabled (-Wc,-ansi_for_scope,on), the definition in (1) is no
longer in scope at (2) and thus the definition in (2) is legal.
int main() {
int sum = 0;
for (int k = 0; k!=100; ++k) // (1)
sum += k;
for (int k = 100; k!= 0; ++k) // (2)
sum += k;
}
112 Command-Line Options