当我为ios编译librtmp时，脚本显示如下：

#!/bin/sh

# OS X Yosemite, Xcode 6.1

set -ex

DEVELOPER="/Applications/Xcode.app/Contents/Developer"
DEVICE_SDK="$DEVELOPER/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk"
SIMULATOR_SDK="$DEVELOPER/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk"
CURRPATH=`pwd`
SOURCE="rtmpdump"
DSTDIR="librtmp"
LIBSSL=`cd ../OpenSSL/libssl;pwd`
ARCHS="i386 x86_64 armv7 armv7s arm64"

rm -rf $DSTDIR
mkdir $DSTDIR

if [ ! -d $SOURCE ]; then
    git clone git://git.ffmpeg.org/rtmpdump $SOURCE
else
    cd $SOURCE
    git fetch
    cd ..
fi

cd $SOURCE/librtmp

for ARCH in $ARCHS; do
    mkdir -p ../$DSTDIR/$ARCH

    if [[ $ARCH == arm* ]]; then
        SDK=$DEVICE_SDK
    else
        SDK=$SIMULATOR_SDK
    fi

    perl -i -pe 's|^AR=\$\(CROSS_COMPILE\)ar|AR=xcrun ar|' Makefile

    CROSS_COMPILE="$DEVELOPER/usr/bin/" \
    XCFLAGS="-O0 -isysroot $SDK -I$LIBSSL/include -arch $ARCH " \
    XLDFLAGS="-isysroot $SDK -L$LIBSSL/lib -arch $ARCH -miphoneos-version-min=7.0 " \
    make SYS=darwin
    make SYS=darwin prefix="$CURRPATH/$DSTDIR/$ARCH" install
    make clean
done

mkdir -p $CURRPATH/$DSTDIR/lib
cd $CURRPATH/$DSTDIR/$ARCH/lib
LIBS=`ls *.a`
cd $CURRPATH
for LIB in $LIBS; do
    lipo -create `find $DSTDIR -name $LIB` -output $DSTDIR/lib/$LIB
done

cp -rf $DSTDIR/$ARCH/include $DSTDIR

for ARCH in $ARCHS; do
    rm -rf $DSTDIR/$ARCH
done

字符串
当语句make SYS=darwin运行时，错误显示：

/Applications/Xcode.app/Contents/Developer/usr/bin/gcc -Wall -O0 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk -I/Users/Smeegol/Desktop/AVCodecs2/OpenSSL/libssl/include -arch armv7   -DRTMPDUMP_VERSION=\"v2.4\" -DUSE_OPENSSL  -O2 -fPIC   -c -o rtmp.o rtmp.c
clang: error: invalid version number in '-miphoneos-version-min=.sd'
make: *** [rtmp.o] Error 1

型
为什么？我设置了XLDFLAGS="-isysroot $SDK -L$LIBSSL/lib -arch $ARCH -miphoneos-version-min=7.0 "，为什么会出现invalid version number in '-miphoneos-version-min=.sd'？