first implementation recognizes when a function declaration is an
explicit function template specialization (based on the presence of a
template<> header), performs template argument deduction + ambiguity
resolution to determine which template is being specialized, and hooks
There are many caveats here:
- We completely and totally drop any explicitly-specified template
arguments on the floor
- We don't diagnose any of the extra semantic things that we should
diagnose.
- I haven't looked to see that we're getting the right linkage for
explicit specializations
On a happy note, this silences a bunch of errors that show up in
libstdc++'s <iostream>, although Clang still can't get through the
entire header.
llvm-svn: 82728