diff --git a/t/sanity.t b/t/sanity.t
index 23e6e51..86f8645 100644
--- a/t/sanity.t
+++ b/t/sanity.t
@@ -1267,8 +1267,8 @@ install: all
 clean:
 	rm -rf build
 --- err
-Can't exec "gcc-4.2": No such file or directory at ./configure line 614.
-Can't exec "gcc-4.2": No such file or directory at ./configure line 649.
+Can't exec "gcc-4.2": No such file or directory at ./configure line 615.
+Can't exec "gcc-4.2": No such file or directory at ./configure line 653.
 
 
 
@@ -1432,8 +1432,8 @@ install: all
 clean:
 	rm -rf build
 --- err
-Can't exec "cl": No such file or directory at ./configure line 614.
-Can't exec "cl": No such file or directory at ./configure line 649.
+Can't exec "cl": No such file or directory at ./configure line 615.
+Can't exec "cl": No such file or directory at ./configure line 653.
 
 
 
@@ -2204,7 +2204,7 @@ install: all
 clean:
 	rm -rf build
 --- err
-Can't exec "sw_vers": No such file or directory at ./configure line 699.
+Can't exec "sw_vers": No such file or directory at ./configure line 712.
 
 
 
@@ -2286,7 +2286,7 @@ install: all
 clean:
 	rm -rf build
 --- err
-Can't exec "sw_vers": No such file or directory at ./configure line 699.
+Can't exec "sw_vers": No such file or directory at ./configure line 712.
 
 
 
@@ -3173,8 +3173,8 @@ cp -rp bundle/ build
 cd build
 cd LuaJIT-2.1-20170405
 INFO: found -msse4.2 in cc.
-gmake TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-DLUAJIT_USE_VALGRIND -DLUAJIT_ENABLE_LUA52COMPAT -msse4.2' CC=cc PREFIX=/usr/local/openresty/luajit
-gmake install TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-DLUAJIT_USE_VALGRIND -DLUAJIT_ENABLE_LUA52COMPAT -msse4.2' CC=cc PREFIX=/usr/local/openresty/luajit DESTDIR=$OPENRESTY_BUILD_DIR/luajit-root/
+gmake TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-DLUAJIT_ENABLE_LUA52COMPAT -msse4.2 -DLUAJIT_USE_VALGRIND' CC=cc PREFIX=/usr/local/openresty/luajit
+gmake install TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-DLUAJIT_ENABLE_LUA52COMPAT -msse4.2 -DLUAJIT_USE_VALGRIND' CC=cc PREFIX=/usr/local/openresty/luajit DESTDIR=$OPENRESTY_BUILD_DIR/luajit-root/
 export LUAJIT_LIB='$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/lib'
 export LUAJIT_INC='$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1'
 cd ..
@@ -3209,14 +3209,14 @@ Type the following commands to build and install:
 .PHONY: all install clean
 
 all:
-	cd $OPENRESTY_BUILD_DIR/LuaJIT-2.1-20170405 && $(MAKE) TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-DLUAJIT_USE_VALGRIND -DLUAJIT_ENABLE_LUA52COMPAT -msse4.2' CC=cc PREFIX=/usr/local/openresty/luajit
+	cd $OPENRESTY_BUILD_DIR/LuaJIT-2.1-20170405 && $(MAKE) TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-DLUAJIT_ENABLE_LUA52COMPAT -msse4.2 -DLUAJIT_USE_VALGRIND' CC=cc PREFIX=/usr/local/openresty/luajit
 	cd $OPENRESTY_BUILD_DIR/lua-cjson-2.1.0.5 && $(MAKE) DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_CMODULE_DIR=/usr/local/openresty/lualib LUA_MODULE_DIR=/usr/local/openresty/lualib CJSON_CFLAGS="-g -fpic" CC=cc
 	cd $OPENRESTY_BUILD_DIR/lua-redis-parser-0.13 && $(MAKE) DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_LIB_DIR=/usr/local/openresty/lualib CC=cc
 	cd $OPENRESTY_BUILD_DIR/lua-rds-parser-0.06 && $(MAKE) DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_LIB_DIR=/usr/local/openresty/lualib CC=cc
 	cd $OPENRESTY_BUILD_DIR/nginx-1.11.2 && $(MAKE)
 
 install: all
-	cd $OPENRESTY_BUILD_DIR/LuaJIT-2.1-20170405 && $(MAKE) install TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-DLUAJIT_USE_VALGRIND -DLUAJIT_ENABLE_LUA52COMPAT -msse4.2' CC=cc PREFIX=/usr/local/openresty/luajit DESTDIR=$(DESTDIR)
+	cd $OPENRESTY_BUILD_DIR/LuaJIT-2.1-20170405 && $(MAKE) install TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-DLUAJIT_ENABLE_LUA52COMPAT -msse4.2 -DLUAJIT_USE_VALGRIND' CC=cc PREFIX=/usr/local/openresty/luajit DESTDIR=$(DESTDIR)
 	cd $OPENRESTY_BUILD_DIR/lua-cjson-2.1.0.5 && $(MAKE) install DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_CMODULE_DIR=/usr/local/openresty/lualib LUA_MODULE_DIR=/usr/local/openresty/lualib CJSON_CFLAGS="-g -fpic" CC=cc
 	cd $OPENRESTY_BUILD_DIR/lua-redis-parser-0.13 && $(MAKE) install DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_LIB_DIR=/usr/local/openresty/lualib CC=cc
 	cd $OPENRESTY_BUILD_DIR/lua-rds-parser-0.06 && $(MAKE) install DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_LIB_DIR=/usr/local/openresty/lualib CC=cc
@@ -3253,8 +3253,8 @@ cp -rp bundle/ build
 cd build
 cd LuaJIT-2.1-20170405
 INFO: found -msse4.2 in cc.
-gmake TARGET_STRIP=@: CCDEBUG=-g Q= XCFLAGS='-DLUAJIT_USE_VALGRIND -DLUAJIT_ENABLE_LUA52COMPAT -msse4.2 -DLUA_USE_APICHECK -DLUA_USE_ASSERT' CC=cc PREFIX=/usr/local/openresty/luajit
-gmake install TARGET_STRIP=@: CCDEBUG=-g Q= XCFLAGS='-DLUAJIT_USE_VALGRIND -DLUAJIT_ENABLE_LUA52COMPAT -msse4.2 -DLUA_USE_APICHECK -DLUA_USE_ASSERT' CC=cc PREFIX=/usr/local/openresty/luajit DESTDIR=$OPENRESTY_BUILD_DIR/luajit-root/
+gmake TARGET_STRIP=@: CCDEBUG=-g Q= XCFLAGS='-DLUAJIT_ENABLE_LUA52COMPAT -msse4.2 -DLUA_USE_APICHECK -DLUA_USE_ASSERT -DLUAJIT_USE_VALGRIND' CC=cc PREFIX=/usr/local/openresty/luajit
+gmake install TARGET_STRIP=@: CCDEBUG=-g Q= XCFLAGS='-DLUAJIT_ENABLE_LUA52COMPAT -msse4.2 -DLUA_USE_APICHECK -DLUA_USE_ASSERT -DLUAJIT_USE_VALGRIND' CC=cc PREFIX=/usr/local/openresty/luajit DESTDIR=$OPENRESTY_BUILD_DIR/luajit-root/
 export LUAJIT_LIB='$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/lib'
 export LUAJIT_INC='$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1'
 cd ..
@@ -3290,14 +3290,14 @@ Type the following commands to build and install:
 .PHONY: all install clean
 
 all:
-	cd $OPENRESTY_BUILD_DIR/LuaJIT-2.1-20170405 && $(MAKE) TARGET_STRIP=@: CCDEBUG=-g Q= XCFLAGS='-DLUAJIT_USE_VALGRIND -DLUAJIT_ENABLE_LUA52COMPAT -msse4.2 -DLUA_USE_APICHECK -DLUA_USE_ASSERT' CC=cc PREFIX=/usr/local/openresty/luajit
+	cd $OPENRESTY_BUILD_DIR/LuaJIT-2.1-20170405 && $(MAKE) TARGET_STRIP=@: CCDEBUG=-g Q= XCFLAGS='-DLUAJIT_ENABLE_LUA52COMPAT -msse4.2 -DLUA_USE_APICHECK -DLUA_USE_ASSERT -DLUAJIT_USE_VALGRIND' CC=cc PREFIX=/usr/local/openresty/luajit
 	cd $OPENRESTY_BUILD_DIR/lua-cjson-2.1.0.5 && $(MAKE) DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_CMODULE_DIR=/usr/local/openresty/lualib LUA_MODULE_DIR=/usr/local/openresty/lualib CJSON_CFLAGS="-g -O -fpic" CC=cc
 	cd $OPENRESTY_BUILD_DIR/lua-redis-parser-0.13 && $(MAKE) DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_LIB_DIR=/usr/local/openresty/lualib CFLAGS="-g -O -Wall" CC=cc
 	cd $OPENRESTY_BUILD_DIR/lua-rds-parser-0.06 && $(MAKE) DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_LIB_DIR=/usr/local/openresty/lualib CFLAGS="-g -O -Wall" CC=cc
 	cd $OPENRESTY_BUILD_DIR/nginx-1.11.2 && $(MAKE)
 
 install: all
-	cd $OPENRESTY_BUILD_DIR/LuaJIT-2.1-20170405 && $(MAKE) install TARGET_STRIP=@: CCDEBUG=-g Q= XCFLAGS='-DLUAJIT_USE_VALGRIND -DLUAJIT_ENABLE_LUA52COMPAT -msse4.2 -DLUA_USE_APICHECK -DLUA_USE_ASSERT' CC=cc PREFIX=/usr/local/openresty/luajit DESTDIR=$(DESTDIR)
+	cd $OPENRESTY_BUILD_DIR/LuaJIT-2.1-20170405 && $(MAKE) install TARGET_STRIP=@: CCDEBUG=-g Q= XCFLAGS='-DLUAJIT_ENABLE_LUA52COMPAT -msse4.2 -DLUA_USE_APICHECK -DLUA_USE_ASSERT -DLUAJIT_USE_VALGRIND' CC=cc PREFIX=/usr/local/openresty/luajit DESTDIR=$(DESTDIR)
 	cd $OPENRESTY_BUILD_DIR/lua-cjson-2.1.0.5 && $(MAKE) install DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_CMODULE_DIR=/usr/local/openresty/lualib LUA_MODULE_DIR=/usr/local/openresty/lualib CJSON_CFLAGS="-g -O -fpic" CC=cc
 	cd $OPENRESTY_BUILD_DIR/lua-redis-parser-0.13 && $(MAKE) install DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_LIB_DIR=/usr/local/openresty/lualib CFLAGS="-g -O -Wall" CC=cc
 	cd $OPENRESTY_BUILD_DIR/lua-rds-parser-0.06 && $(MAKE) install DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_LIB_DIR=/usr/local/openresty/lualib CFLAGS="-g -O -Wall" CC=cc
@@ -4223,8 +4223,8 @@ cp -rp bundle/ build
 cd build
 cd LuaJIT-2.1-20170405
 INFO: found -msse4.2 in cc.
-gmake TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-DLUAJIT_ENABLE_LUA52COMPAT -msse4.2' CC=cc PREFIX=/usr/local/openresty/luajit
-gmake install TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-DLUAJIT_ENABLE_LUA52COMPAT -msse4.2' CC=cc PREFIX=/usr/local/openresty/luajit DESTDIR=$OPENRESTY_BUILD_DIR/luajit-root/
+gmake TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-msse4.2 -DLUAJIT_ENABLE_LUA52COMPAT' CC=cc PREFIX=/usr/local/openresty/luajit
+gmake install TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-msse4.2 -DLUAJIT_ENABLE_LUA52COMPAT' CC=cc PREFIX=/usr/local/openresty/luajit DESTDIR=$OPENRESTY_BUILD_DIR/luajit-root/
 export LUAJIT_LIB='$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/lib'
 export LUAJIT_INC='$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1'
 cd ..
@@ -4259,14 +4259,14 @@ Type the following commands to build and install:
 .PHONY: all install clean
 
 all:
-	cd $OPENRESTY_BUILD_DIR/LuaJIT-2.1-20170405 && $(MAKE) TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-DLUAJIT_ENABLE_LUA52COMPAT -msse4.2' CC=cc PREFIX=/usr/local/openresty/luajit
+	cd $OPENRESTY_BUILD_DIR/LuaJIT-2.1-20170405 && $(MAKE) TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-msse4.2 -DLUAJIT_ENABLE_LUA52COMPAT' CC=cc PREFIX=/usr/local/openresty/luajit
 	cd $OPENRESTY_BUILD_DIR/lua-cjson-2.1.0.5 && $(MAKE) DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_CMODULE_DIR=/usr/local/openresty/lualib LUA_MODULE_DIR=/usr/local/openresty/lualib CJSON_CFLAGS="-g -fpic" CC=cc
 	cd $OPENRESTY_BUILD_DIR/lua-redis-parser-0.13 && $(MAKE) DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_LIB_DIR=/usr/local/openresty/lualib CC=cc
 	cd $OPENRESTY_BUILD_DIR/lua-rds-parser-0.06 && $(MAKE) DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_LIB_DIR=/usr/local/openresty/lualib CC=cc
 	cd $OPENRESTY_BUILD_DIR/nginx-1.11.2 && $(MAKE)
 
 install: all
-	cd $OPENRESTY_BUILD_DIR/LuaJIT-2.1-20170405 && $(MAKE) install TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-DLUAJIT_ENABLE_LUA52COMPAT -msse4.2' CC=cc PREFIX=/usr/local/openresty/luajit DESTDIR=$(DESTDIR)
+	cd $OPENRESTY_BUILD_DIR/LuaJIT-2.1-20170405 && $(MAKE) install TARGET_STRIP=@: CCDEBUG=-g XCFLAGS='-msse4.2 -DLUAJIT_ENABLE_LUA52COMPAT' CC=cc PREFIX=/usr/local/openresty/luajit DESTDIR=$(DESTDIR)
 	cd $OPENRESTY_BUILD_DIR/lua-cjson-2.1.0.5 && $(MAKE) install DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_CMODULE_DIR=/usr/local/openresty/lualib LUA_MODULE_DIR=/usr/local/openresty/lualib CJSON_CFLAGS="-g -fpic" CC=cc
 	cd $OPENRESTY_BUILD_DIR/lua-redis-parser-0.13 && $(MAKE) install DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_LIB_DIR=/usr/local/openresty/lualib CC=cc
 	cd $OPENRESTY_BUILD_DIR/lua-rds-parser-0.06 && $(MAKE) install DESTDIR=$(DESTDIR) LUA_INCLUDE_DIR=$OPENRESTY_BUILD_DIR/luajit-root/usr/local/openresty/luajit/include/luajit-2.1 LUA_LIB_DIR=/usr/local/openresty/lualib CC=cc
diff --git a/util/configure b/util/configure
index e78fc74..46ecdfd 100755
--- a/util/configure
+++ b/util/configure
@@ -129,6 +129,7 @@ my @ngx_rpaths;
 my $cc;
 my $cores;
 my $luajit_xcflags = '';
+my $user_luajit_xcflags;
 my $no_luajit_lua52;
 
 my (@ngx_opts, @ngx_cc_opts, @ngx_ld_opts);
@@ -256,7 +257,7 @@ for my $opt (@ARGV) {
         $resty_opts{luajit_path} = $1;
 
     } elsif ($opt =~ /^--with-luajit-xcflags=(.*)/) {
-        $luajit_xcflags .= " $1";
+        $user_luajit_xcflags .= " $1";
 
     } elsif ($opt =~ /^--without-luajit-lua52/) {
         $no_luajit_lua52 = 1;
@@ -621,11 +622,14 @@ _END_
         }
 
         if (!$no_luajit_lua52
-            && (!$luajit_xcflags || $luajit_xcflags !~ /-DLUAJIT_ENABLE_LUA52COMPAT\b/))
+            && (!$user_luajit_xcflags
+                || $user_luajit_xcflags !~ /-DLUAJIT_ENABLE_LUA52COMPAT\b/))
         {
             $luajit_xcflags .= " -DLUAJIT_ENABLE_LUA52COMPAT";
         }
 
+        if (!$user_luajit_xcflags
+            || $user_luajit_xcflags !~ /-msse4\.2\b/)
         {
             # check -msse4.2
             my ($out, $cfile) = tempfile("resty-config-XXXXXX",
@@ -667,10 +671,19 @@ int main(void) {
 
         if ($opts->{debug}) {
             $luajit_xcflags .= " -DLUA_USE_APICHECK -DLUA_USE_ASSERT";
+
+            if ($user_luajit_xcflags) {
+                $luajit_xcflags .= $user_luajit_xcflags;
+            }
             $luajit_xcflags =~ s/^ +//;
+
             $extra_opts .= qq{ Q= XCFLAGS='$luajit_xcflags'};
 
         } else {
+            if ($user_luajit_xcflags) {
+                $luajit_xcflags .= $user_luajit_xcflags;
+            }
+
             if ($luajit_xcflags) {
                 $luajit_xcflags =~ s/^ +//;
                 $extra_opts .= qq{ XCFLAGS='$luajit_xcflags'};