GC not reclaiming impure strings held by macro frames

[Kent M Pitman <KMP @ MIT-MC>]

This message records a discussion I had with RMS regarding a 
probable bug in the Teco GC relating to impure strings held by 
inactive macro frame pointers.

I have a Teco init file for dumping an Emacs which does some setup, 
then does:

  er â—Š @y fsrgettyâ—Š"n@' ftAttempting to macro buffer...â—Š :m(hfx*)â—Š'

The start file which gets loaded is very large (about 5K) and does

  :m(@:i*| -1f? ei@ejâ—Šw@ft
  Dumped to ≥N
  â—Š0fsechoactiveâ—Šw164000.fs exitâ—Š|)

at the end of it so that the 5K string can get reclaimed by the -f?

Unfortunately, if I read the resulting BIN file into an editor and 
search for the 5K start file, I find that the string is still present
and not getting GC'd.