From b3eee1426656bbd3efd7468fd3f6880753847e19 Mon Sep 17 00:00:00 2001
From: Ivan Maidanski <ivmai@mail.ru>
Date: Fri, 31 Aug 2018 19:06:27 +0300
Subject: [PATCH] Eliminate 'comparison is always false' code defect in
 get_maps

In case of a single-threaded build, the comparison is always false
because maps_size>=0 and old_maps_size<=0.

* os_dep.c [NEED_PROC_MAPS] (GC_get_maps): Do not evaluate
maps_size<old_maps_size inside while expression if THREADS; remove
comment.
---
 os_dep.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/os_dep.c b/os_dep.c
index 56e8a84..f0b2bb6 100644
--- a/os_dep.c
+++ b/os_dep.c
@@ -242,8 +242,11 @@ GC_INNER char * GC_get_maps(void)
                      " (to %" WARN_PRIdPTR " bytes)\n", maps_size);
               }
 #           endif
-        } while (maps_size >= maps_buf_sz || maps_size < old_maps_size);
-                /* In the single-threaded case, the second clause is false. */
+        } while (maps_size >= maps_buf_sz
+#                ifdef THREADS
+                   || maps_size < old_maps_size
+#                endif
+                );
         maps_buf[maps_size] = '\0';
         return maps_buf;
 }
-- 
2.7.4