diff --git a/CHANGELOG b/CHANGELOG
index 32822b8..60071a8 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -16,6 +16,9 @@ changed:
  * <arch>-apple-darwinXX-cc/c++ defaults now to clang
  * switched to two-space indents
 
+fixed:
+ * 'MACOSX_DEPLOYMENT_TARGET' env var is now handled correctly
+
 /******************************* v0.6 *******************************/
 
 added:
diff --git a/build.sh b/build.sh
index 5ba0c9c..dd43420 100755
--- a/build.sh
+++ b/build.sh
@@ -315,8 +315,9 @@ rm -f $OSXCROSS_CONF $OSXCROSS_ENV
 echo "compiling wrapper ..."
 
 export OSXCROSS_VERSION
-export OSX_VERSION_MIN
-export LINKER_VERSION
+export OSXCROSS_TARGET=$TARGET
+export OSXCROSS_OSX_VERSION_MIN=$OSX_VERSION_MIN
+export OSXCROSS_LINKER_VERSION=$LINKER_VERSION
 
 if [ "$PLATFORM" != "Darwin" ]; then
   # libLTO.so
@@ -328,7 +329,7 @@ $BASE_DIR/wrapper/build.sh 1>/dev/null
 
 echo ""
 
-if [ -n $OSX_VERSION_MIN ]; then
+if [ "$OSX_VERSION_MIN" != "default" ]; then
   if [ `echo "${SDK_VERSION/u/}<$OSX_VERSION_MIN" | bc -l` -eq 1 ]; then
     echo "OSX_VERSION_MIN must be <= SDK_VERSION"
     trap "" EXIT
diff --git a/build_gcc.sh b/build_gcc.sh
index 0b71307..d981a8a 100755
--- a/build_gcc.sh
+++ b/build_gcc.sh
@@ -12,9 +12,10 @@ source tools/tools.sh
 # GCC version to build
 # (<4.7 will not work properly with libc++)
 GCC_VERSION=4.8.2
+#GCC_VERSION=4.9-20140416 # snapshot
 
 # GCC mirror
-GCC_MIRROR="ftp://ftp.gwdg.de/pub/misc/gcc/releases"
+GCC_MIRROR="ftp://ftp.gwdg.de/pub/misc/gcc"
 
 require wget
 
@@ -30,7 +31,11 @@ source $BASE_DIR/tools/trap_exit.sh
 if [ ! -f "have_gcc_${GCC_VERSION}_${OSXCROSS_TARGET}" ]; then
 
 pushd $OSXCROSS_TARBALL_DIR &>/dev/null
-wget -c "$GCC_MIRROR/gcc-$GCC_VERSION/gcc-$GCC_VERSION.tar.bz2"
+if [[ $GCC_VERSION != *-* ]]; then
+  wget -c "$GCC_MIRROR/releases/gcc-$GCC_VERSION/gcc-$GCC_VERSION.tar.bz2"
+else
+  wget -c "$GCC_MIRROR/snapshots/$GCC_VERSION/gcc-$GCC_VERSION.tar.bz2"
+fi
 popd &>/dev/null
 
 echo "cleaning up ..."
@@ -102,9 +107,9 @@ echo "compiling wrapper ..."
 
 export OSXCROSS_VERSION
 export OSXCROSS_LIBLTO_PATH
-export TARGET=$OSXCROSS_TARGET
-export OSX_VERSION_MIN=$OSXCROSS_OSX_VERSION_MIN
-export LINKER_VERSION=$OSXCROSS_LINKER_VERSION
+export OSXCROSS_TARGET
+export OSXCROSS_OSX_VERSION_MIN=$OSXCROSS_OSX_VERSION_MIN
+export OSXCROSS_LINKER_VERSION=$OSXCROSS_LINKER_VERSION
 
 TARGETCOMPILER=gcc \
   $BASE_DIR/wrapper/build.sh 1>/dev/null
diff --git a/wrapper/build.sh b/wrapper/build.sh
index 7935db1..86f5ed9 100755
--- a/wrapper/build.sh
+++ b/wrapper/build.sh
@@ -5,6 +5,12 @@ pushd .. &>/dev/null
 source ./tools/tools.sh
 popd &>/dev/null
 
+set +e
+if [ -z "$OSXCROSS_VERSION" ]; then
+  `../target/bin/osxcross-conf 2>/dev/null`
+fi
+set -e
+
 EXESUFFIX=""
 
 function create_wrapper_link
@@ -12,12 +18,12 @@ function create_wrapper_link
   verbose_cmd ln -sf "${TARGETTRIPLE}-wrapper${EXESUFFIX}" "${1}${EXESUFFIX}"
 }
 
-[ -z "$TARGET" ] && TARGET=darwin12
-[ -z "$OSX_VERSION_MIN" ] && OSX_VERSION_MIN=10.5
-[ -z "$LINKER_VERSION" ] && LINKER_VERSION=134.9
+[ -z "$OSXCROSS_TARGET" ] && OSXCROSS_TARGET=darwin12
+[ -z "$OSXCROSS_OSX_VERSION_MIN" ] && OSXCROSS_OSX_VERSION_MIN=10.5
+[ -z "$OSXCROSS_LINKER_VERSION" ] && OSXCROSS_LINKER_VERSION=134.9
 [ -z "$TARGETCOMPILER" ] && TARGETCOMPILER=clang
 
-TARGETTRIPLE=x86_64-apple-$TARGET
+TARGETTRIPLE=x86_64-apple-${OSXCROSS_TARGET}
 
 FLAGS=""
 
@@ -61,9 +67,9 @@ function compile_wrapper()
 
   verbose_cmd $CXX compiler.cpp -std=c++0x -pedantic -Wall -Wextra \
     "-DOSXCROSS_VERSION=\"\\\"$OSXCROSS_VERSION\\\"\"" \
-    "-DOSXCROSS_TARGET=\"\\\"$TARGET\\\"\"" \
-    "-DOSXCROSS_OSX_VERSION_MIN=\"\\\"$OSX_VERSION_MIN\\\"\"" \
-    "-DOSXCROSS_LINKER_VERSION=\"\\\"$LINKER_VERSION\\\"\"" \
+    "-DOSXCROSS_TARGET=\"\\\"$OSXCROSS_TARGET\\\"\"" \
+    "-DOSXCROSS_OSX_VERSION_MIN=\"\\\"$OSXCROSS_OSX_VERSION_MIN\\\"\"" \
+    "-DOSXCROSS_LINKER_VERSION=\"\\\"$OSXCROSS_LINKER_VERSION\\\"\"" \
     "-DOSXCROSS_LIBLTO_PATH=\"\\\"$OSXCROSS_LIBLTO_PATH\\\"\"" \
     -o "../target/bin/${TARGETTRIPLE}-wrapper${EXESUFFIX}" -O2 \
     $FLAGS $*
@@ -82,13 +88,13 @@ if [ $TARGETCOMPILER = "clang" ]; then
   create_wrapper_link o64-clang++
   create_wrapper_link o64-clang++-libc++
 
-  create_wrapper_link i386-apple-$TARGET-clang
-  create_wrapper_link i386-apple-$TARGET-clang++
-  create_wrapper_link i386-apple-$TARGET-clang++-libc++
+  create_wrapper_link i386-apple-${OSXCROSS_TARGET}-clang
+  create_wrapper_link i386-apple-${OSXCROSS_TARGET}-clang++
+  create_wrapper_link i386-apple-${OSXCROSS_TARGET}-clang++-libc++
 
-  create_wrapper_link x86_64-apple-$TARGET-clang
-  create_wrapper_link x86_64-apple-$TARGET-clang++
-  create_wrapper_link x86_64-apple-$TARGET-clang++-libc++
+  create_wrapper_link x86_64-apple-${OSXCROSS_TARGET}-clang
+  create_wrapper_link x86_64-apple-${OSXCROSS_TARGET}-clang++
+  create_wrapper_link x86_64-apple-${OSXCROSS_TARGET}-clang++-libc++
 elif [ $TARGETCOMPILER = "gcc" ]; then
   create_wrapper_link o32-gcc
   create_wrapper_link o32-g++
@@ -98,42 +104,42 @@ elif [ $TARGETCOMPILER = "gcc" ]; then
   create_wrapper_link o64-g++
   create_wrapper_link o64-g++-libc++
 
-  create_wrapper_link i386-apple-$TARGET-gcc
-  create_wrapper_link i386-apple-$TARGET-g++
-  create_wrapper_link i386-apple-$TARGET-g++-libc++
+  create_wrapper_link i386-apple-${OSXCROSS_TARGET}-gcc
+  create_wrapper_link i386-apple-${OSXCROSS_TARGET}-g++
+  create_wrapper_link i386-apple-${OSXCROSS_TARGET}-g++-libc++
 
-  create_wrapper_link x86_64-apple-$TARGET-gcc
-  create_wrapper_link x86_64-apple-$TARGET-g++
-  create_wrapper_link x86_64-apple-$TARGET-g++-libc++
+  create_wrapper_link x86_64-apple-${OSXCROSS_TARGET}-gcc
+  create_wrapper_link x86_64-apple-${OSXCROSS_TARGET}-g++
+  create_wrapper_link x86_64-apple-${OSXCROSS_TARGET}-g++-libc++
 fi
 
-create_wrapper_link i386-apple-$TARGET-cc
-create_wrapper_link i386-apple-$TARGET-c++
+create_wrapper_link i386-apple-${OSXCROSS_TARGET}-cc
+create_wrapper_link i386-apple-${OSXCROSS_TARGET}-c++
 
-create_wrapper_link x86_64-apple-$TARGET-cc
-create_wrapper_link x86_64-apple-$TARGET-c++
+create_wrapper_link x86_64-apple-${OSXCROSS_TARGET}-cc
+create_wrapper_link x86_64-apple-${OSXCROSS_TARGET}-c++
 
 create_wrapper_link osxcross-conf
-create_wrapper_link i386-apple-$TARGET-osxcross-conf
-create_wrapper_link x86_64-apple-$TARGET-osxcross-conf
+create_wrapper_link i386-apple-${OSXCROSS_TARGET}-osxcross-conf
+create_wrapper_link x86_64-apple-${OSXCROSS_TARGET}-osxcross-conf
 
 create_wrapper_link osxcross-env
-create_wrapper_link i386-apple-$TARGET-osxcross-env
-create_wrapper_link x86_64-apple-$TARGET-osxcross-env
+create_wrapper_link i386-apple-${OSXCROSS_TARGET}-osxcross-env
+create_wrapper_link x86_64-apple-${OSXCROSS_TARGET}-osxcross-env
 
 create_wrapper_link osxcross
-create_wrapper_link i386-apple-$TARGET-osxcross
-create_wrapper_link x86_64-apple-$TARGET-osxcross
+create_wrapper_link i386-apple-${OSXCROSS_TARGET}-osxcross
+create_wrapper_link x86_64-apple-${OSXCROSS_TARGET}-osxcross
 
 if [ "$PLATFORM" != "Darwin" ]; then
   create_wrapper_link sw_vers
-  create_wrapper_link i386-apple-$TARGET-sw_vers
-  create_wrapper_link x86_64-apple-$TARGET-sw_vers
+  create_wrapper_link i386-apple-${OSXCROSS_TARGET}-sw_vers
+  create_wrapper_link x86_64-apple-${OSXCROSS_TARGET}-sw_vers
 fi
 
 create_wrapper_link dsymutil
-create_wrapper_link i386-apple-$TARGET-dsymutil
-create_wrapper_link x86_64-apple-$TARGET-dsymutil
+create_wrapper_link i386-apple-${OSXCROSS_TARGET}-dsymutil
+create_wrapper_link x86_64-apple-${OSXCROSS_TARGET}-dsymutil
 
 popd &>/dev/null
 popd &>/dev/null
diff --git a/wrapper/compiler.cpp b/wrapper/compiler.cpp
index bc054a5..9d74888 100644
--- a/wrapper/compiler.cpp
+++ b/wrapper/compiler.cpp
@@ -29,9 +29,6 @@
  *
  * Debug messages can be enabled by setting 'OCDEBUG' (ENV) to 1.
  *
- * TODO:
- *  - handle MACOSX_DEPLOYMENT_TARGET (env)
- *
  */
 
 #include "compat.h"
@@ -429,8 +426,8 @@ private:
 
 struct OSVersion {
   constexpr OSVersion(int major, int minor, int patch = 0)
-      : major(major), minor(minor), patch(patch) {}
-  constexpr OSVersion() : major(), minor(), patch() {}
+      : major(major), minor(minor), patch(patch), s() {}
+  constexpr OSVersion() : major(), minor(), patch(), s() {}
 
   constexpr int Num() const {
     return major * 10000 + minor * 100 + patch;
@@ -490,6 +487,7 @@ struct OSVersion {
   int major;
   int minor;
   int patch;
+  char s[12];
 };
 
 static_assert(OSVersion(10, 6) != OSVersion(10, 5), "");
@@ -657,6 +655,11 @@ struct Target {
   bool hasLibCXX() const { return getSDKOSNum() >= OSVersion(10, 7); }
 
   bool libCXXIsDefaultCXXLib() const {
+    OSVersion OSNum = this->OSNum;
+
+    if (!OSNum.Num())
+      OSNum = getSDKOSNum();
+
     return stdlib != libstdcxx && hasLibCXX() && OSNum >= OSVersion(10, 9);
   }
 
@@ -988,7 +991,6 @@ struct Target {
         break;
 
       if (usegcclibs) {
-#ifndef _WIN32
         // Use libs from './build_gcc.sh' installation
 
         CXXHeaderPath += "/../../";
@@ -1017,10 +1019,6 @@ struct Target {
         CXXHeaderPath += gccversion.Str();
 
         addCXXPath(otriple);
-#else
-        std::cerr << "'-oc-use-gcc-libs' not implemented" << std::endl;
-        return false;
-#endif
       } else {
         // Use SDK libs
         std::string tmp;
@@ -1261,7 +1259,8 @@ struct Target {
 // Program 'sw_vers'
 //
 
-__attribute__((noreturn)) void prog_sw_vers(int argc, char **argv) {
+__attribute__((noreturn)) void prog_sw_vers(int argc, char **argv,
+                                            const Target &target) {
 
   auto genFakeBuildVer = [](std::string & build)->std::string & {
     std::stringstream tmp;
@@ -1281,16 +1280,22 @@ __attribute__((noreturn)) void prog_sw_vers(int argc, char **argv) {
     return build;
   };
 
-  auto getProductVer = []()->OSVersion {
+  auto getProductVer = [&]()->OSVersion {
     char *p = getenv("OSXCROSS_SW_VERS_OSX_VERSION");
+    OSVersion OSNum;
 
     if (!p)
       p = getenv("MACOSX_DEPLOYMENT_TARGET");
 
     if (p)
-      return parseOSVersion(p);
+      OSNum = parseOSVersion(p);
+    else
+      OSNum = getDefaultMinTarget();
 
-    return getDefaultMinTarget();
+    if (!OSNum.Num())
+      OSNum = target.getSDKOSNum();
+
+    return OSNum;
   };
 
   if (argc == 2) {
@@ -1337,6 +1342,7 @@ __attribute__((noreturn)) void prog_osxcross(int argc, char **argv) {
 
 __attribute__((noreturn)) void prog_osxcross_conf(const Target &target) {
   std::string sdkpath;
+  OSVersion OSXVersionMin = getDefaultMinTarget();
   const char *ltopath = getLibLTOPath();
 
   if (!target.getSDKPath(sdkpath)) {
@@ -1344,12 +1350,15 @@ __attribute__((noreturn)) void prog_osxcross_conf(const Target &target) {
     exit(EXIT_FAILURE);
   }
 
+  if (!OSXVersionMin.Num())
+    OSXVersionMin = target.getSDKOSNum();
+
   if (!ltopath)
     ltopath = "";
 
   std::cout << "export OSXCROSS_VERSION=" << getOSXCrossVersion() << std::endl;
-  std::cout << "export OSXCROSS_OSX_VERSION_MIN="
-            << getDefaultMinTarget().shortStr() << std::endl;
+  std::cout << "export OSXCROSS_OSX_VERSION_MIN=" << OSXVersionMin.shortStr()
+            << std::endl;
   std::cout << "export OSXCROSS_TARGET=" << getDefaultTarget() << std::endl;
   std::cout << "export OSXCROSS_SDK_VERSION=" << target.getSDKOSNum().shortStr()
             << std::endl;
@@ -1574,6 +1583,11 @@ bool detectTarget(int argc, char **argv, Target &target) {
       return val;
     };
 
+    if (char *p = getenv("MACOSX_DEPLOYMENT_TARGET")) {
+      target.OSNum = parseOSVersion(p);
+      unsetenv("MACOSX_DEPLOYMENT_TARGET");
+    }
+
     for (int i = 1; i < argc; ++i) {
       char *arg = argv[i];
 
@@ -1624,6 +1638,7 @@ bool detectTarget(int argc, char **argv, Target &target) {
           std::cerr << "warning: '" << arg << "' has no effect" << std::endl;
           continue;
         }
+        target.stdlib = StdLib::libstdcxx;
         target.usegcclibs = true;
       } else if (!strncmp(arg, "-o", 2)) {
         target.outputname = getVal(arg, "-o", i);
@@ -1695,7 +1710,7 @@ bool detectTarget(int argc, char **argv, Target &target) {
   };
 
   if (!strcmp(cmd, "sw_vers"))
-    prog_sw_vers(argc, argv);
+    prog_sw_vers(argc, argv, target);
   else if (!strcmp(cmd, "osxcross"))
     prog_osxcross(argc, argv);
   else if (!strcmp(cmd, "osxcross-env"))
@@ -1737,7 +1752,7 @@ bool detectTarget(int argc, char **argv, Target &target) {
       else if (target.compiler == "wrapper")
         exit(EXIT_SUCCESS);
       else if (target.compiler == "sw_vers")
-        prog_sw_vers(argc, argv);
+        prog_sw_vers(argc, argv, target);
       else if (target.compiler == "osxcross")
         prog_osxcross(argc, argv);
       else if (target.compiler == "osxcross-env")
diff --git a/wrapper/oscompat.h b/wrapper/oscompat.h
index 154da43..ec53f70 100644
--- a/wrapper/oscompat.h
+++ b/wrapper/oscompat.h
@@ -10,5 +10,7 @@ int setenv(const char *name, const char *value, int overwrite) {
 
   return putenv(buf.c_str());
 }
+
+int unsetenv(const char *name) { return setenv(name, "", 1); }
 #endif
 }