[xmlsec] Little logic error

[Igor Zlatkovic]

Hi there,

There is a small error of mine in include/xmlsec/errors.h regarding the
__FUNCTION__ logic. The current predicate is

   #if !defined(__GNUC__) || (_MSC_VER >= 1300)

which I wrongly assumed would work, on a gloomy day well past midnight. In
fact, this predicate always fires on everything other than GNUC, because
__GNUC__ is not defined.

The truth is, that the correct predicate cannot be conducted generally, but
every offending compiler must bring its own toys. That brings us to
something like

   #if defined(__A_COMPILER__) && (__A_COMPILER__ < X)
   #define __FUNCTION__ ""
   #endif

with "__A_COMPILER__" being whatever the current compiler predefines. Every
compiler brand which does not support __FUNCTION__ will need its own
construct like the above.

I now fixed the predicate to handle the MSVC compiler version lower than 13.
If there is someone using a compiler other than GNUC or MSVC, please drop me
a correct predicate for your compiler, if it doesn't support the builtin
__FUNCTION__ macro.

Or does someone have a better idea?

Ciao
Igor