Re: [PATCH][C++] Fix PR29433, make C++ use a lot less time/memory

[Nathan Sidwell <nathan at codesourcery dot com>]

Jason Merrill wrote:

> When we see the first T in "T T();" we have no idea that it's supposed 
> to be a type-specifier, so we can't look it up specially.

I don't understand, we must be looking it up specially, otherwise the struct 
stat hack wouldn't work.

Except for cdtors & conversion ops, declarations have a leading type specifier 
right?  So the first T in 'T T()' should be looked up as a type specifier? 
Otherwise I don't see how

int T;
struct S {
	struct T {};
	T T ();  // #1
};
is being parsed (we accept that).  Why are we allowing the first T in #1 to 
lookup the type tag 'struct S::T' and not the decl '::T'?

But we reject the following:
struct S {
  int T;
  struct T {};
  T baz ();
};

yuck!

nathan

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