From e593fef3206c359344c93bf7a3716da644f1906f Mon Sep 17 00:00:00 2001
From: Araq <rumpf_a@web.de>
Date: Wed, 3 Jan 2018 13:24:20 +0100
Subject: [PATCH] memfiles: better error checking for Windows; refs #6361

---
 lib/pure/memfiles.nim | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/lib/pure/memfiles.nim b/lib/pure/memfiles.nim
index 9b2d252675..5c73381ffb 100644
--- a/lib/pure/memfiles.nim
+++ b/lib/pure/memfiles.nim
@@ -257,10 +257,13 @@ proc close*(f: var MemFile) =
   when defined(windows):
     if f.wasOpened:
       error = unmapViewOfFile(f.mem) == 0
-      lastErr = osLastError()
-      error = (closeHandle(f.mapHandle) == 0) or error
-      if f.fHandle != INVALID_HANDLE_VALUE:
-        error = (closeHandle(f.fHandle) == 0) or error
+      if not error:
+        error = closeHandle(f.mapHandle) == 0
+        if not error and f.fHandle != INVALID_HANDLE_VALUE:
+          discard closeHandle(f.fHandle)
+          f.fHandle = INVALID_HANDLE_VALUE
+      if error:
+        lastErr = osLastError()
   else:
     error = munmap(f.mem, f.size) != 0
     lastErr = osLastError()