Comment 7 for bug 632368

I have a case where I'd like compiler macros to be retried not only on
a constant argument, but basically in any case a compiler macro depends
on &ENVIRONMENT because the inlining could have caused transplanting
the call form into a new lexenv where a MACROLET or SYMBOL-MACROLET
is active.

I use this stuff to optimize special variable access (the general case) into
lexical variable access by saving information at compile-time about whether
a suitable lexical variable is available.