From 52172d234015776bcc595c731477b98fa2949e50 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Sat, 14 Sep 2019 10:55:53 -0700
Subject: [PATCH] Fix gc-elapsed rounding bug
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* src/alloc.c (garbage_collect): Don’t accumulate rounding
errors when computing gc-elapsed.
---
 src/alloc.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/alloc.c b/src/alloc.c
index 497f600551e..9fbd0d05739 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -6021,9 +6021,10 @@ garbage_collect (void)
   /* Accumulate statistics.  */
   if (FLOATP (Vgc_elapsed))
     {
-      struct timespec since_start = timespec_sub (current_timespec (), start);
-      Vgc_elapsed = make_float (XFLOAT_DATA (Vgc_elapsed)
-				+ timespectod (since_start));
+      static struct timespec gc_elapsed;
+      gc_elapsed = timespec_add (gc_elapsed,
+				 timespec_sub (current_timespec (), start));
+      Vgc_elapsed = make_float (timespectod (gc_elapsed));
     }
 
   gcs_done++;
-- 
2.39.5