destroy_thread now processes guardian entries

original commit: 9bcf0a10c1a1c12d93a8eabb061821377de0934f

LOG

@@ -438,3 +438,5 @@
   of the same to the COMMAND-LINE OPTIONS section of the man page.
   did a bit of minor cleanup elsewhere in the man page.
     use.stex, scheme.1.in
+- destroy_thread now processes guardian entries
+    thread.c, 4.ms, release_notes.stex

c/thread.c

@@ -172,6 +172,21 @@ static IBOOL destroy_thread(tc) ptr tc; {
      /* process remembered set before dropping allocation area */
       S_scan_dirty((ptr **)EAP(tc), (ptr **)REAL_EAP(tc));
 
+     /* process guardian entries */
+      {
+	ptr target, ges, obj, next; seginfo *si;
+	target = S_G.guardians[0];
+	for (ges = GUARDIANENTRIES(tc); ges != Snil; ges = next) {
+	  obj = GUARDIANOBJ(ges);
+	  next = GUARDIANNEXT(ges);
+	  if (!IMMEDIATE(obj) && (si = MaybeSegInfo(ptr_get_segment(obj))) != NULL && si->generation != static_generation) {
+	    INITGUARDIANNEXT(ges) = target;
+	    target = ges;
+	  }
+	}
+	S_G.guardians[0] = target;
+      }
+
      /* deactivate thread */
       if (ACTIVE(tc)) {
         SETSYMVAL(S_G.active_threads_id,
@@ -185,6 +200,7 @@ static IBOOL destroy_thread(tc) ptr tc; {
       free((void *)THREADTC(thread));
       THREADTC(thread) = 0; /* mark it dead */
       status = 1;
+      break;
     }
     ls = &Scdr(*ls);
   }

mats/4.ms

@@ -2992,6 +2992,17 @@
              (collect 0 0)
              (list ((g1)) p)))))
      '((c d) (b)))
+
+   (or (not (threaded?))
+       (equal?
+         (parameterize ([collect-request-handler void])
+           (let ([g (make-guardian)])
+             (fork-thread (lambda () (g (list 'a 'b))))
+             (let f () (when (> #%$active-threads 1) (f)))
+             (collect)
+             (g)))
+         '(a b)))
+
    (parameterize ([collect-request-handler void] [enable-object-counts #t])
      (define-record-type fraz (fields zle))
      (define g (make-guardian))

release_notes/release_notes.stex

@@ -1490,6 +1490,12 @@ in fasl files does not generally make sense.
 %-----------------------------------------------------------------------------
 \section{Bug Fixes}\label{section:bugfixes}
 
+\subsection{Missing guardian entries when a thread exits (9.4.1)}
+
+A bug that causes guardian entries for a thread to be lost when a
+thread exits has been fixed.
+[This bug dated back to Version 6.5.]
+
 \subsection{Incorrect code for certain nested \protect\scheme{if} patterns (9.4.1)}
 
 A bug in the source optimizer that produced incorrect code for certain