Re: Legacy compiler that should (but doesn't) work
On Tuesday, 19 March 2013 06:00:03 UTC, Jerry wrote:
Consider this:
template<class X>
int operator==(const X& x, const char *y)
{ return 1; }
template<class X,class Y>
int operator==(const X& x, const Y& y)
{ return 2; }
struct A {} a;
main()
{
return a == "a";
}
GCC compiles this with no problem and returns 1 (which I want).
That looks like a bug in G++ to me. Argument deduction should work
for both templates, with the resulting function signatures:
A const&, char const*
and
A const&, char const (&)[2]
I rather think this is ambiguous (but I'd have to reread the standard
to be sure), but if not, the second function would be a better match.
But the compiler I have to use (AIX xlC version 6) is not so smart.
It looks smarter than g++ in this case.
[...]
What I want to do is so easy and would take no real effort with a
modern compiler. I hate being stuck with a compiler that is more
than 10 years old but I don't have a choice.
The rules here haven't changed since C++98 (and xlC was always one of
the best and most advanced with regards to templates---at least back
then).
--
James
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