Re: Fix, GDL2, EOQualifier (getKey()): args

[David Ayers]

Tim McIntosh schrieb:
> 
> 1. After passing ap to another function by value, it is not valid to use
> ap in the caller without re-initializing it.  Currently
> _qualifierWithArgs() is violating this rule by passing 'args' in two
> sequential calls to getKey().
> 
> 2. It is valid to do this if ap is instead passed by pointer (as in the
> original code and proposed changes).
> 
> 3. Taking the address of a va_list that has been passed by value is
> unportable (see GCC bug comment #14).  The original code and the
> proposed changes do this.  It looks like this could be fixed by changing
> _qualifierWithArgs() to take 'va_list *' instead of 'va_list' and
> eliminating (or similarly changing the signature of)
> -qualifierWithQualifierFormat:varargList:.

Thanks for the summary!  Redefining the EOF API is not something that
lies in our power :-)

But I'm wondering whether we can play some platform specific typedef
games in that file like:

#ifdef x86_64||ppc64
# Well the above should actually be an autoconf variable that simply
# test during configure which approach works better.
typedef va_list va_list_ref;
#else
typedef va_list *va_list_ref;
#endif

... with some special preparation for the va_list * case in
-qualifierWithQualifierFormat:varargList:.

I currently don't have either platform available for testing but I
suspect we'll have some patches to play with in a bit...

Cheers,
David