diff --git a/configure b/configure
index b188055143..86571546fc 100755
--- a/configure
+++ b/configure
@@ -1404,18 +1404,6 @@ while [ "$#" -gt 0 ]; do
         unixware7-g++)
             PLATFORM=unixware-g++
             ;;
-        macx-g++-64)
-            PLATFORM=macx-g++
-	    NATIVE_64_ARCH=
-            case `uname -p` in
-            i386) NATIVE_64_ARCH="x86_64" ;;
-            powerpc) NATIVE_64_ARCH="ppc64" ;;
-            *)   echo "WARNING: Can't detect CPU architecture for macx-g++-64" ;;
-            esac
-	    if [ ! -z "$NATIVE_64_ARCH" ]; then
-		QTCONFIG_CONFIG="$QTCONFIG_CONFIG $NATIVE_64_ARCH"
-            fi
-            ;;
         esac
         ;;
     xplatform)
@@ -3199,13 +3187,13 @@ if [ "$XPLATFORM_ANDROID" = "yes" ]; then
             ;;
         macx-*)
             CFG_DEFAULT_ANDROID_NDK_HOST=darwin-x86
-            if [ ! -z "$NATIVE_64_ARCH" ] && [ -d "$CFG_DEFAULT_ANDROID_NDK_ROOT/toolchains/arm-linux-androideabi-$CFG_DEFAULT_ANDROID_NDK_TOOLCHAIN_VERSION/prebuilt/darwin-x86_64" ]; then
+            if [ -d "$CFG_DEFAULT_ANDROID_NDK_ROOT/toolchains/arm-linux-androideabi-$CFG_DEFAULT_ANDROID_NDK_TOOLCHAIN_VERSION/prebuilt/darwin-x86_64" ]; then
                 CFG_DEFAULT_ANDROID_NDK_HOST=darwin-x86_64
             fi
             ;;
         win32-*)
             CFG_DEFAULT_ANDROID_NDK_HOST=windows
-            if [ ! -z "$NATIVE_64_ARCH" ] && [ -d "$CFG_DEFAULT_ANDROID_NDK_ROOT/toolchains/arm-linux-androideabi-$CFG_DEFAULT_ANDROID_NDK_TOOLCHAIN_VERSION/prebuilt/windows-x86_64" ]; then
+            if [ -d "$CFG_DEFAULT_ANDROID_NDK_ROOT/toolchains/arm-linux-androideabi-$CFG_DEFAULT_ANDROID_NDK_TOOLCHAIN_VERSION/prebuilt/windows-x86_64" ]; then
                 CFG_DEFAULT_ANDROID_NDK_HOST=windows-x86_64
             fi
             ;;
diff --git a/mkspecs/features/mac/default_post.prf b/mkspecs/features/mac/default_post.prf
index b459389c72..7100717b78 100644
--- a/mkspecs/features/mac/default_post.prf
+++ b/mkspecs/features/mac/default_post.prf
@@ -1,20 +1,7 @@
 load(default_post)
 !no_objective_c:CONFIG += objective_c
 
-qt:!isEmpty(QT_CONFIG) {
-    # Pick a suitable default architecture for qmake-based applications.
-    # If the Qt package contains one of x86 and x86_64, pick that one. If it
-    # contains both then use the compiler default. Make a similar decision for
-    # PowerPC-based systems. Note that this logic assumes that Qt has been
-    # configured with an architecture that is usable on the system.
-    contains(QMAKE_HOST.arch, ppc)|contains(QMAKE_HOST.arch, "Power Macintosh") {
-        !contains(QT_CONFIG, ppc64):contains(QT_CONFIG, ppc):CONFIG += ppc
-        contains(QT_CONFIG, ppc64):!contains(QT_CONFIG, ppc):CONFIG += ppc64
-    } else {
-        !contains(QT_CONFIG, x86_64):contains(QT_CONFIG, x86):CONFIG += x86
-        contains(QT_CONFIG, x86_64):!contains(QT_CONFIG, x86):CONFIG += x86_64
-    }
-
+qt {
     contains(QT_CONFIG, static) {
         # C++11 support means using libc++ instead of libstd++. As the
         # two libraries are incompatible we need to ensure the end user