Hey Monks,

I have an XS module which has worked for years, but is giving me warnings with a new compiler:

        for (i = 0; i < n; i++) {
            HE *he = hv_iternext (hv);

            STRLEN key_len;
>>>         char *key = HePV (he, key_len);

[download]
Utils.xs:263:13: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]

The offending line is: "char *key = HePV (he, key_len);"

I've resolved some similar errors by changing the type of the LHS variable. But in this case, (char *) seems to be the absolutely correct type. Presumably it's because HePV is a macro that maps to a complicated nested ternary variable structure which maybe contains a subtle mix of types?

Can I do anything, other than perhaps just turning off warnings for this?

In reply to Calling HePV - "warning: dereferencing type-punned pointer will break strict-aliasing rules" by the.jxc

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