From 386e208eb887a7e832ff28f271c368579d417154 Mon Sep 17 00:00:00 2001
From: Justin Ethier <justin.ethier@gmail.com>
Date: Mon, 6 Aug 2018 14:48:37 -0400
Subject: [PATCH] Revert previous changed

noticed an intermittent crash running read1
---
 gc.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/gc.c b/gc.c
index 28a7ebe4..0d30ccbe 100644
--- a/gc.c
+++ b/gc.c
@@ -541,7 +541,7 @@ size_t gc_convert_heap_page_to_free_list(gc_heap *h, gc_thread_data *thd)
 gc_heap *gc_sweep_fixed_size(gc_heap * h, int heap_type, gc_thread_data *thd)
 {
   short heap_is_empty;
-  object p, end;
+  object p;
   gc_free_list *q, *r, *s;
 #if GC_DEBUG_SHOW_SWEEP_DIAG
   gc_heap *orig_heap_ptr = h;
@@ -567,15 +567,14 @@ gc_heap *gc_sweep_fixed_size(gc_heap * h, int heap_type, gc_thread_data *thd)
     size_t remaining = h->size - (h->size % h->block_size); // - h->block_size; // Remove first one??
     char *data_end = h->data + remaining;
     heap_is_empty = 1; // Base case is an empty heap
-    end = (object)data_end;
-    p = h->data;
     q = h->free_list;
-    while (p < end) {
+    while (remaining) {
+      p = data_end - remaining;
       // find preceding/succeeding free list pointers for p
       for (r = (q?q->next:NULL); r && ((char *)r < (char *)p); q = r, r = r->next) ;
       if ((char *)q == (char *)p || (char *)r == (char *)p) {     // this is a free block, skip it
         //printf("Sweep skip free block %p remaining=%lu\n", p, remaining);
-        p = (object) (((char *)p) + h->block_size);
+        remaining -= h->block_size;
         continue;
       }
 #if GC_SAFETY_CHECKS
@@ -649,7 +648,7 @@ gc_heap *gc_sweep_fixed_size(gc_heap * h, int heap_type, gc_thread_data *thd)
       }
       //next->next = (gc_free_list *)(((char *) next) + h->block_size);
       //next = next->next;
-      p = (object) (((char *)p) + h->block_size);
+      remaining -= h->block_size;
     }
   }
   // Free the heap page if possible.