diff --git a/configure/os/CONFIG.Common.win32-x86-mingw b/configure/os/CONFIG.Common.win32-x86-mingw
index a8390e6ef..8b83bf5b0 100644
--- a/configure/os/CONFIG.Common.win32-x86-mingw
+++ b/configure/os/CONFIG.Common.win32-x86-mingw
@@ -9,6 +9,7 @@ include $(CONFIG)/os/CONFIG.Common.UnixCommon
 
 OS_CLASS = WIN32
 ARCH_CLASS = x86
+POSIX = NO
 
 #  Definitions used when COMMANDLINE_LIBRARY is READLINE
 LDLIBS_READLINE = -lreadline -lcurses
diff --git a/configure/os/CONFIG.linux-x86.windows-x64-mingw b/configure/os/CONFIG.linux-x86.windows-x64-mingw
new file mode 100644
index 000000000..3692d6cb2
--- /dev/null
+++ b/configure/os/CONFIG.linux-x86.windows-x64-mingw
@@ -0,0 +1,22 @@
+# CONFIG.linux-x86.windows-x64-mingw
+#
+# Definitions for linux-x86 host windows-x64-mingw target builds
+# Override these definitions in CONFIG_SITE.linux-x86.windows-x64-mingw
+#-------------------------------------------------------
+
+# Include common gnu compiler definitions
+include $(CONFIG)/CONFIG.gnuCommon
+
+# Add resource compiler
+RCCMD = $(GNU_BIN)/$(CMPLR_PREFIX)windres$(CMPLR_SUFFIX) $(INCLUDES) $< $@
+
+# Remove -fPIC flags, add out-implib
+SHRLIB_CFLAGS =
+SHRLIB_LDFLAGS = -shared -Wl,--out-implib,$(LIB_PREFIX)$*$(LIB_SUFFIX)
+LOADABLE_SHRLIB_LDFLAGS = -shared -Wl,--out-implib,$(LIB_PREFIX)$*$(LIB_SUFFIX)
+
+# No need to explicitly link with gcc library
+GNU_LDLIBS_YES =
+
+# Link with system libraries
+OP_SYS_LDLIBS = -lws2_32 -ladvapi32 -luser32 -lkernel32 -lwinmm
diff --git a/configure/os/CONFIG.linux-x86_64.windows-x64-mingw b/configure/os/CONFIG.linux-x86_64.windows-x64-mingw
new file mode 100644
index 000000000..f84301266
--- /dev/null
+++ b/configure/os/CONFIG.linux-x86_64.windows-x64-mingw
@@ -0,0 +1,9 @@
+# CONFIG.linux-x86_64.windows-x64-mingw
+#
+# Definitions for linux-x86_64 host windows-x64-mingw target builds
+# Override these definitions in CONFIG_SITE.linux-x86_64.windows-x64-mingw
+#-------------------------------------------------------
+
+# Settings as for the linux-x86 host architecture
+include $(CONFIG)/os/CONFIG.linux-x86.windows-x64-mingw
+
diff --git a/configure/os/CONFIG_SITE.linux-x86.win32-x86-mingw b/configure/os/CONFIG_SITE.linux-x86.win32-x86-mingw
index 1d132b74d..cb624242b 100644
--- a/configure/os/CONFIG_SITE.linux-x86.win32-x86-mingw
+++ b/configure/os/CONFIG_SITE.linux-x86.win32-x86-mingw
@@ -5,10 +5,9 @@
 
 # Early versions of the MinGW cross-build tools can only build
 # static (non-DLL) libraries. Fedora's cross-build of gcc 4.4.6
-# needs these uncommented, other distributions have not been
-# tested with this release of Base:
-SHARED_LIBRARIES = NO
-STATIC_BUILD = YES
+# needs these uncommented, cross-gcc 4.6.3 for Ubuntu does not:
+#SHARED_LIBRARIES = NO
+#STATIC_BUILD = YES
 
 # The cross-build tools are in $(GNU_DIR)/bin
 # Default is /usr
@@ -21,3 +20,6 @@ STATIC_BUILD = YES
 CMPLR_PREFIX = i686-pc-mingw32-
 # Debian?
 #CMPLR_PREFIX = i586-mingw32msvc-
+
+# Use static compiler-support libraries
+OP_SYS_LDFLAGS += -static-libgcc -static-libstdc++
diff --git a/configure/os/CONFIG_SITE.linux-x86.windows-x64-mingw b/configure/os/CONFIG_SITE.linux-x86.windows-x64-mingw
new file mode 100644
index 000000000..026410cfe
--- /dev/null
+++ b/configure/os/CONFIG_SITE.linux-x86.windows-x64-mingw
@@ -0,0 +1,23 @@
+# CONFIG_SITE.linux-x86.windows-x64-mingw
+#
+# Configuration for linux-x86 host windows-x64-mingw target builds
+#-------------------------------------------------------
+
+# Early versions of the MinGW cross-build tools can only build
+# static (non-DLL) libraries. For example RHEL's cross-gcc 4.4.6
+# needs these uncommented, cross-gcc 4.6.3 for Ubuntu does not:
+#SHARED_LIBRARIES = NO
+#STATIC_BUILD = YES
+
+# The cross-build tools are in $(GNU_DIR)/bin
+# Default is /usr
+#GNU_DIR = /usr/local
+
+# Different distribution cross-build packages use different prefixes:
+# Ubuntu:
+#CMPLR_PREFIX = i686-w64-mingw32-
+# RHEL:
+CMPLR_PREFIX = x86_64-w64-mingw32-
+
+# Use static compiler-support libraries
+OP_SYS_LDFLAGS += -static-libgcc -static-libstdc++
diff --git a/configure/os/CONFIG_SITE.linux-x86_64.windows-x64-mingw b/configure/os/CONFIG_SITE.linux-x86_64.windows-x64-mingw
new file mode 100644
index 000000000..e98ac7a02
--- /dev/null
+++ b/configure/os/CONFIG_SITE.linux-x86_64.windows-x64-mingw
@@ -0,0 +1,8 @@
+# CONFIG_SITE.linux-x86_64.windows-x64-mingw
+#
+# Configuration for linux-x86_64 host windows-x64-mingw target builds
+#-------------------------------------------------------
+
+# Inherit from the linux-x86 host architecture
+include $(CONFIG)/os/CONFIG_SITE.linux-x86.windows-x64-mingw
+
diff --git a/documentation/RELEASE_NOTES.html b/documentation/RELEASE_NOTES.html
index 10daf1016..bf44e11ab 100644
--- a/documentation/RELEASE_NOTES.html
+++ b/documentation/RELEASE_NOTES.html
@@ -13,6 +13,37 @@
 
 <!-- Insert new items immediately below here ... -->
 
+<h3>MinGW Cross-builds from Linux</h3>
+
+<p>Build configuration files have been back-ported from the 3.15 branch that
+allow cross-building of the windows-x64-mingw target from either linux-x86 or
+linux-x86_64 hosts. Similar support for the 32-bit win32-x86-mingw cross-target
+was added in Base-3.14.12.5. Adjust the settings in the configuration file
+configure/os/CONFIG_SITE.linux-x86.windows-x64-mingw and add windows-x64-mingw
+to the CROSS_COMPILER_TARGET_ARCHS variable in configure/CONFIG_SITE or in
+configure/os/CONFIG_SITE.linux-x86.Common.</p>
+
+<p>The Linux MinGW cross-builds now use the compiler flags <tt>-static-libgcc
+-static-libstdc++</tt> which avoids having to copy some DLLs onto the Windows
+system to be able to run the generated binaries. These compiler flags can be
+disabled by editing the configure/os/CONFIG_SITE.linux-x86.<i>target</i> file
+for Linux distributions where the cross-build toolset doesn't make static
+versions of those libraries available. The RHEL-6.8 MinGW toolset does not
+package a static version of the library winpthread-1 so on that host OS it is
+still necessary to provide a copy of the libwinpthread-1.dll file for the
+Windows system to use. The simplest way to do this is to manually copy it into
+the IOC application's bin/win32-x86-mingw or bin/windows-x64-mingw directory
+after building the IOC, like this (note that Windows DLLs are always installed
+into the bin directory, not the lib directory):</p>
+
+<blockquote><pre>
+<b>$</b> cp /usr/i686-w64-mingw32/sys-root/mingw/bin/libwinpthread-1.dll bin/win32-x86-mingw
+<b>$</b> cp /usr/x86_64-w64-mingw32/sys-root/mingw/bin/libwinpthread-1.dll bin/windows-x64-mingw
+</pre></blockquote>
+
+<p>Some additional MinGW-specific changes have also been back-ported from the
+Base-3.15 branch.</p>
+
 <h3>General Time updates</h3>
 
 <p>The <tt>iocInit</tt> code now performs a sanity check of the current time
diff --git a/src/libCom/osi/os/WIN32/epicsGetopt.c b/src/libCom/osi/os/WIN32/epicsGetopt.c
index 97bb11f47..1ea064ea2 100644
--- a/src/libCom/osi/os/WIN32/epicsGetopt.c
+++ b/src/libCom/osi/os/WIN32/epicsGetopt.c
@@ -1,3 +1,5 @@
+#ifndef _MINGW
+
 /*
  * Copyright (c) 1987, 1993, 1994
  *	The Regents of the University of California.  All rights reserved.
@@ -121,3 +123,5 @@ int getopt(nargc, nargv, ostr)
 	}
 	return (optopt);			/* dump back option letter */
 }
+
+#endif /* !_MINGW */
diff --git a/src/libCom/osi/os/WIN32/epicsGetopt.h b/src/libCom/osi/os/WIN32/epicsGetopt.h
index aa3bc7422..f92041085 100644
--- a/src/libCom/osi/os/WIN32/epicsGetopt.h
+++ b/src/libCom/osi/os/WIN32/epicsGetopt.h
@@ -12,6 +12,12 @@
 #ifndef _EPICS_GETOPT_H
 #define _EPICS_GETOPT_H
 
+#ifdef _MINGW
+
+#include <unistd.h>
+
+#else /* _MINGW */
+
 #include "shareLib.h"
 
 #ifdef __cplusplus
@@ -28,4 +34,6 @@ epicsShareExtern int optind, opterr, optopt;
 }
 #endif
 
+#endif /* _MINGW */
+
 #endif /* _EPICS_GETOPT_H */
diff --git a/src/libCom/osi/os/WIN32/osdThread.c b/src/libCom/osi/os/WIN32/osdThread.c
index 7f3d34500..5f61fc894 100644
--- a/src/libCom/osi/os/WIN32/osdThread.c
+++ b/src/libCom/osi/os/WIN32/osdThread.c
@@ -92,7 +92,7 @@ static const int osdRealtimePriorityList [osdRealtimePriorityStateCount] =
 
 #if !defined(EPICS_DLL_NO)
 BOOL WINAPI DllMain (
-    HANDLE hModule, DWORD dwReason, LPVOID lpReserved )
+    HINSTANCE hModule, DWORD dwReason, LPVOID lpReserved )
 {
     static DWORD dllHandleIndex;
     HMODULE dllHandle = 0;