[PATCH] Fix up LD_* vars behaviour

[Roland McGrath]

> If they are documenting the tool, and their documentation is accurate,
> then it's a valid reference point for what we are allowed to change on
> people or not.

No, it's not.  What the past behavior was is what matters, regardless of
whether or where it was ever documented.  We are quite conservative in
changing any existing behavior that some user may have depended on.  But
in cases where there is not a clear specification such as POSIX or ISO C
indicating the detail should never have been relied upon, then it's
entirely a question of our judgment about what is better for users overall.


Thanks,
Roland