bug#15688: 24.3.50; clear-temporary-overlay-map

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

It crashed again.  This time the slot pointed to was again in
Fgarbage_collect, but it was 80(sp).  That's where the variable
message_p (char) is stored.  The value of message_p is 0,
but it happens that the low 8 bits of the address of clear-temporary-map
are zero, so storing the value of message_p into that byte didn't
alter the pointer in the word.

What seems fishy here is that clear-temporary-map still points to
that vectorlike even though the vectorlike has been freed.
Maybe that's where the real bug is.  Why didn't this code

#if GC_MARK_STACK
                symbol_free_list->function = Vdead;
#endif

prevent the problem?

-- 
Dr Richard Stallman
President, Free Software Foundation
51 Franklin St
Boston MA 02110
USA
www.fsf.org  www.gnu.org
Skype: No way! That's nonfree (freedom-denying) software.
  Use Ekiga or an ordinary phone call.