iOS库的libxml2链接错误

Question

在C库上进行处理，导致与architecure有关的链接错误。我正在尝试为iOS构建库，但它依赖libxml2，在这种情况下，我猜这是Mac唯一的库

lipo -info确认相同

admin $ lipo -info /usr/local/lib/libxml2.dylib非胖文件：/usr/local/lib/libxml2.dylib是体系结构：x86_64

ld：警告：忽略文件/usr/local/lib/libxml2.dylib，该文件是为x86_64（不是链接的体系结构）构建的（armv7）：/usr/local/lib/libxml2.dylib体系结构armv7的未定义符号：“ _xmlAddChild”，引用自：libspatialite.a中的_setIsoId（gg_xml.o）引用：libspatialite.a中的_vxpath_eval_expr（libsplite_la-virtualxpath.o）ld：找不到体系结构armv7 clang的符号：错误：链接器命令失败退出代码1（使用-v查看调用）make [4]： * [demo1]错误1 make [3]： [install-recursive]错误1 make [2]： [install-strip]错误2生成1 ：* [/Users/admin/Downloads/libspatialite-ios-master/build/armv7/lib/libspatialite.a]错误2生成：*** [build_arches]错误2

编辑＃1

注释完make文件中的libspatailite配置和make部分后，我注意到所有平台armv7，armv7s，arm64，i386，x86_64的其余依赖项（如gets，proj，sqlite）都已生成。

这些库上的lipo -info确认相同。因此问题仅限于构建libspatialite。

Makefile（仅生成libspatialite.a）

XCODE_DEVELOPER = $(shell xcode-select --print-path)
IOS_PLATFORM ?= iPhoneOS

# Pick latest SDK in the directory
IOS_PLATFORM_DEVELOPER = ${XCODE_DEVELOPER}/Platforms/${IOS_PLATFORM}.platform/Developer
IOS_SDK = ${IOS_PLATFORM_DEVELOPER}/SDKs/$(shell ls ${IOS_PLATFORM_DEVELOPER}/SDKs | sort -r | head -n1)

all: lib/libspatialite.a
lib/libspatialite.a: build_arches
    mkdir -p lib
    mkdir -p include

    # Copy includes
    cp -R build/armv7/include/geos include
    cp -R build/armv7/include/spatialite include
    cp -R build/armv7/include/*.h include

    # Make fat libraries for all architectures
    for file in build/armv7/lib/*.a; \
        do name=`basename $$file .a`; \
        lipo -create \
            -arch armv7 build/armv7/lib/$$name.a \
            -arch armv7s build/armv7s/lib/$$name.a \
            -arch arm64 build/arm64/lib/$$name.a \
            -arch i386 build/i386/lib/$$name.a \
            -arch x86_64 build/x86_64/lib/$$name.a \
            -output lib/$$name.a \
        ; \
        done;

# Build separate architectures
build_arches:
    ${MAKE} arch ARCH=armv7 IOS_PLATFORM=iPhoneOS HOST=arm-apple-darwin
    ${MAKE} arch ARCH=armv7s IOS_PLATFORM=iPhoneOS HOST=arm-apple-darwin
    ${MAKE} arch ARCH=arm64 IOS_PLATFORM=iPhoneOS HOST=arm-apple-darwin
    ${MAKE} arch ARCH=i386 IOS_PLATFORM=iPhoneSimulator HOST=i386-apple-darwin
    ${MAKE} arch ARCH=x86_64 IOS_PLATFORM=iPhoneSimulator HOST=x86_64-apple-darwin

PREFIX = ${CURDIR}/build/${ARCH}
LIBDIR = ${PREFIX}/lib
BINDIR = ${PREFIX}/bin
INCLUDEDIR = ${PREFIX}/include

CXX = ${XCODE_DEVELOPER}/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++
CC = ${XCODE_DEVELOPER}/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang
CFLAGS = -isysroot ${IOS_SDK} -I${IOS_SDK}/usr/include -arch ${ARCH} -I${INCLUDEDIR} -miphoneos-version-min=7.0
CXXFLAGS = -stdlib=libc++ -std=c++11 -isysroot ${IOS_SDK} -I${IOS_SDK}/usr/include -arch ${ARCH} -I${INCLUDEDIR} -miphoneos-version-min=7.0
LDFLAGS = -stdlib=libc++ -isysroot ${IOS_SDK} -L${LIBDIR} -L${IOS_SDK}/usr/lib -arch ${ARCH} -miphoneos-version-min=7.0

arch: ${LIBDIR}/libspatialite.a

${LIBDIR}/libspatialite.a: ${LIBDIR}/libproj.a ${LIBDIR}/libgeos.a ${LIBDIR}/libsqlite3.a ${CURDIR}/spatialite
    cd spatialite && env \
    CXX=${CXX} \
    CC=${CC} \
    CFLAGS="${CFLAGS} -Wno-error=implicit-function-declaration" \
    CXXFLAGS="${CXXFLAGS} -Wno-error=implicit-function-declaration" \
    LDFLAGS="${LDFLAGS} -liconv -lgeos -lgeos_c -lc++" ./configure --host=${HOST} --disable-freexl --prefix=${PREFIX} --with-geosconfig=${BINDIR}/geos-config --disable-shared && make clean install-strip


clean:
    rm -rf build geos proj spatialite sqlite3 include lib

@ gagan-ios，@ kristina-brooks-似乎spaceite目录中的Makefile是从Makefile上面自动生成的。我不确定如何控制lib，包括libxml2的动态路径。

Edit2进一步的调查显示，为i386和x86_64生成库，而为armv7，armv7s和arm64生成库失败

$ {MAKE}拱ARCH = armv7 IOS_PLATFORM = iPhoneOS HOST = arm-apple-darwin $ {MAKE}拱ARCH = armv7s IOS_PLATFORM = iPhoneOS HOST = arm-apple-darwin $ {MAKE}拱ARCH = arm64 IOS_PLATFORM = iPhoneOS HOST = arm -apple-darwin $ {MAKE}拱ARCH = i386 IOS_PLATFORM = iPhoneSimulator HOST = i386-apple-darwin $ {MAKE}拱ARCH = x86_64 IOS_PLATFORM = iPhoneSimulator HOST = x86_64-apple-darwin

Answer 1

iPhoneOS SDK中应该存在一个合适的libxml2存根，只需将-lxml2添加到链接器标志中就可以了。 我猜您已经为libxml2.dylib明确指定了绝对路径，而不是让链接器使用SDK相对路径，因此您正尝试从OS发行版中将ARM静态库链接到libxml2的x86_64版本。

Answer 2

最终能够在Makefile的帮助下找到解决方法，用于编译与iOS项目一起使用的外部C ++库

解决方法是将2个不同的make文件合并在一起，并涉及以下步骤。

1.部分使用Makefile为所有平台生成依赖关系的库（pros，geos，sqlite3） https://github.com/gstf/libspatialite-ios

2.使用来自编译外部C ++库的Makefile从源代码编译 libxml2 以用于iOS项目

3. 编译用于iOS项目的外部C ++库中的 Makefile用于生成所有平台的spatialite库

4，使用步骤1 Makefile中的lipo生成Fat库

#!/bin/bash

PLATFORMPATH="/Applications/Xcode.app/Contents/Developer/Platforms"
TOOLSPATH="/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin"
export IPHONEOS_DEPLOYMENT_TARGET="8.0"
pwd=`pwd`

findLatestSDKVersion()
{
    sdks=`ls $PLATFORMPATH/$1.platform/Developer/SDKs`
    arr=()
    for sdk in $sdks
    do
       arr[${#arr[@]}]=$sdk
    done

    # Last item will be the current SDK, since it is alpha ordered
    count=${#arr[@]}
    if [ $count -gt 0 ]; then
       sdk=${arr[$count-1]:${#1}}
       num=`expr ${#sdk}-4`
       SDKVERSION=${sdk:0:$num}
    else
       SDKVERSION="8.0"
    fi
}

buildit()
{
    target=$1
    hosttarget=$1
    platform=$2

    if [[ $hosttarget == "x86_64" ]]; then
        hostarget="i386"
    elif [[ $hosttarget == "arm64" ]]; then
        hosttarget="arm"
    fi

    export CC="$(xcrun -sdk iphoneos -find clang)"
    export CPP="$CC -E"
    export CFLAGS="-arch ${target} -isysroot $PLATFORMPATH/$platform.platform/Developer/SDKs/$platform$SDKVERSION.sdk -miphoneos-version-min=$SDKVERSION"
    export AR=$(xcrun -sdk iphoneos -find ar)
    export RANLIB=$(xcrun -sdk iphoneos -find ranlib)
    export CPPFLAGS="-arch ${target}  -isysroot $PLATFORMPATH/$platform.platform/Developer/SDKs/$platform$SDKVERSION.sdk -miphoneos-version-min=$SDKVERSION"
    export LDFLAGS="-arch ${target} -isysroot $PLATFORMPATH/$platform.platform/Developer/SDKs/$platform$SDKVERSION.sdk"

    mkdir -p $pwd/output/$target

     ./configure --prefix="$pwd/output/$target" --disable-shared --disable-sqlite --host=$hosttarget-apple-darwin

    make clean
    make
    make install
}

findLatestSDKVersion iPhoneOS

buildit armv7 iPhoneOS
buildit armv7s iPhoneOS
buildit arm64 iPhoneOS
buildit i386 iPhoneSimulator
buildit x86_64 iPhoneSimulator

将这些库添加到新的Xcode项目中并开始使用它。 好吧，这是我使用此库的第一个成功

包括这些库

#include <sqlite3.h>
#include <spatialite/gaiageo.h>
#include <spatialite.h>

使用以下API获取Spatialite版本

spatialite_init(0);
printf("Spatialite version: %s\n", spatialite_version());

产量

Spatialite version: 4.3.0