__lib_stack_end

[Roland McGrath]

> - Am I right about this symbols history?

I believe so.

> - Is using dlsym to bypass the 2.1 -> PRIVATE -> 2.1 switch kosher?

I don't know what kind of kosher you are asking about.  It is true that
dlsym ignores symbol versions, so you will see any exported symbol, even
one in the GLIBC_PRIVATE version set.

> - Is there any chance of getting an officially exported __libc_stack_end
>   equivalent?

Yes, we would like to make it reasonable for libraries like Boehm's to
get the information they need through an interface that is clearly kosher.
What exists today is pthread_getattr_np and pthread_attr_getstack.
If these are reported not to work on the initial thread, we will fix that.
It is obviously not ideal that the only access to this be in -lpthread,
since one might not be using threads at all and prefer not to bring it in.
I'm open to suggestions.