$NetBSD: patch-configure,v 1.1 2017/07/04 13:50:42 jperkin Exp $

Shell portability.

--- configure.orig	2015-09-23 12:34:56.000000000 +0000
+++ configure
@@ -5983,7 +5983,7 @@ then
 $as_echo "$as_me: g++ is really clang++" >&6;}
    using_clang=yes
 fi
-if test x$CXX == "xclang++" ; then
+if test x$CXX = "xclang++" ; then
    using_clang=yes
 fi
 
@@ -6000,7 +6000,7 @@ if test x"${mingw}" != "xyes" ; then
   C_WARNINGS_TO_TEST="$C_WARNINGS_TO_TEST -Wall -Wstrict-prototypes"
 fi
 
-if test $using_clang == "no" ; then
+if test $using_clang = "no" ; then
   # -Wstrict-null-sentinel is not supported under clang
   CXX_WARNINGS_TO_TEST="$CXX_WARNINGS_TO_TEST -Wstrict-null-sentinel"
 fi
@@ -6431,7 +6431,7 @@ $as_echo "#define __LINUX__ 1" >>confdef
      ;;
 esac
 
-if test x"${mingw}" == "xno" ; then
+if test x"${mingw}" = "xno" ; then
   # Bring additional directories where things might be found into our
   # search path. I don't know why autoconf doesn't do this by default
   for spfx in /usr/local /opt/local /sw /usr/local/ssl /usr/boost/include ; do
@@ -6453,7 +6453,7 @@ $as_echo "$as_me:  LDFLAGS = ${LDFLAGS} 
 fi
 
 if test -r /bin/uname.exe ; then
-  if test "`uname -o`" == "Msys" ; then
+  if test "`uname -o`" = "Msys" ; then
     { $as_echo "$as_me:${as_lineno-$LINENO}: Compiling with Msys. Setting flags appropriately." >&5
 $as_echo "$as_me: Compiling with Msys. Setting flags appropriately." >&6;}
     LIBS="$LIBS -lws2_32 -lgdi32"