[Bug c++/15144] Template instantiation can't find symbol in global namespace

[giovannibajo at libero dot it]

------- Additional Comments From giovannibajo at libero dot it  2004-04-27 00:49 -------
Well, if I say T::baz the lookup is obviously deferred at instantiation time 
because the name is dependent. 

The point here is Koenig lookup. In templates, there is a special kind of 
Koenig lookup which is evaluated at instantiation time. If you say "baz(x)" 
where x is dependent, GCC will do a normal unqualified lookup of "baz" at 
parsing time, and a Koenig lookup in the associated namespaces of "x" at 
instantiation time. This is why the code works in that case. Instead, if you 
say "::baz(x)" you disable Koenig lookup (which only applies to unqualified 
names), so the only lookup performed is the one at parsing time: nothing is 
found and an error is emitted.

I hope this clarifies the issue.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15144