From 2662ba54494e37074bbc0fc7e4b3eafdd793e98e Mon Sep 17 00:00:00 2001
From: Jason Evans <jasone@canonware.com>
Date: Wed, 12 Aug 2015 11:10:42 -0700
Subject: [PATCH] Stop forcing --enable-munmap on MinGW.

This is no longer necessary because of the more general chunk
merge/split approach to dealing with map coalescing.
---
 INSTALL      | 5 +----
 configure.ac | 4 ----
 2 files changed, 1 insertion(+), 8 deletions(-)

diff --git a/INSTALL b/INSTALL
index 5413ae86..8d396874 100644
--- a/INSTALL
+++ b/INSTALL
@@ -150,10 +150,7 @@ any of the following arguments (not a definitive list) to 'configure':
     the virtual memory for later use.  munmap() is disabled by default (i.e.
     --disable-munmap is implied) on Linux, which has a quirk in its virtual
     memory allocation algorithm that causes semi-permanent VM map holes under
-    normal jemalloc operation.  Conversely, munmap() (actually VirtualFree()) is
-    forcefully enabled on MinGW because virtual memory mappings do not
-    automatically coalesce (nor fragment on demand), and extra bookkeeping
-    would be required to track mapping boundaries.
+    normal jemalloc operation.
 
 --disable-fill
     Disable support for junk/zero filling of memory, quarantine, and redzones.
diff --git a/configure.ac b/configure.ac
index 6f44b6c3..f7c7f3ce 100644
--- a/configure.ac
+++ b/configure.ac
@@ -881,10 +881,6 @@ fi
 ],
 [enable_munmap="${default_munmap}"]
 )
-if test "x$enable_munmap" = "x0" -a "x${maps_coalesce}" = "x0" ; then
-  AC_MSG_RESULT([Forcing munmap to avoid non-coalescing map issues])
-  enable_munmap="1"
-fi
 if test "x$enable_munmap" = "x1" ; then
   AC_DEFINE([JEMALLOC_MUNMAP], [ ])
 fi