Cross-compile Autotools-based Libraries for Official iPhone SDK

Question

Background

I am writing a program that targets several different phones, including the iPhone. The program depends on several thirdparty libraries. I am having difficulty cross-compiling these thirdparty libraries for the iPhone and iPhone simulator. The libraries include the Apache Portable Runtime and GNUTLS, as well as their dependencies. I would like the built libraries to end up in the prefixes "/opt/iphone-3.1", "/opt/iphone-3.0", "/opt/iphone-2.2.1", "/opt/iphone-simulator-3.1", and "/opt/iphone-simulator-3.0", respectively.

In order to make the cross-compilation process easily repeatable, I am creating scripts to invoke the "configure" script for each of the target platforms ("iphone3.1-configure", "iphone3.0-configure", "iphone2.2.1-configure", "iphonesim3.1-configure", and "iphonesim3.0-configure"). This is where I am having trouble.

I am using a Mac OS X 10.6 Snow Leopard computer with the official Xcode 3.2 + iPhone SDK 3.1.

Status

I currently have the following "iphone3.1-configure" script:

#! /bin/bash

#
# Program  : iphone3.1-configure
# Author   : Michael Aaron Safyan
# Synopsis :
#            This program runs the "configure" script generated by the
#            GNU Autotools in order to cross-compile thirdparty libraries
#            for the iPhone 3.1 SDK. Run this script while in a directory
#            containing an autotools "configure" script. Once run, this
#            you can use "make" and "sudo make install" to build the library.
#            An install prefix of "/opt/iphone-3.1/" is used.
#

unset CPATH
unset C_INCLUDE_PATH
unset CPLUS_INCLUDE_PATH
unset OBJC_INCLUDE_PATH
unset LIBS
unset DYLD_FALLBACK_LIBRARY_PATH
unset DYLD_FALLBACK_FRAMEWORK_PATH

export BUILD_DARWIN_VER=`uname -r`
export SDKVER="3.1"
export DEVROOT="/Developer/Platforms/iPhoneOS.platform/Developer"
export SDKROOT="$DEVROOT/SDKs/iPhoneOS$SDKVER.sdk"
export PKG_CONFIG_PATH=/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS$SDKVER.sdk/usr/lib/pkgconfig:/Developer/Platforms/iPhoneOS.platform/Developer/usr/lib/pkgconfig:/opt/iphone-$SDKVER/lib/pkgconfig:/usr/local/iphone-$SDKVER/lib/pkgconfig
export PREFIX="/opt/iphone-$SDKVER"
export AS="$DEVROOT/usr/bin/as"
export ASCPP="$DEVROOT/usr/bin/as"
export AR="$DEVROOT/usr/bin/ar"
export RANLIB="$DEVROOT/usr/bin/ranlib"
export CPPFLAGS="-std=c99 -arch armv6 -pipe -no-cpp-precomp --sysroot='$SDKROOT' -isystem $SDKROOT/usr/include -isystem $DEVROOT/usr/include -isystem /opt/iphone-$SDKVER/include -isystem /usr/local/iphone-$SDKVER/include"
export CFLAGS="-std=c99 -arch armv6 -pipe -no-cpp-precomp --sysroot='$SDKROOT' -isystem $SDKROOT/usr/include -isystem $DEVROOT/usr/include -isystem /opt/iphone-$SDKVER/include -isystem /usr/local/iphone-$SDKVER/include"
export CXXFLAGS="-std=c99 -arch armv6 -pipe -no-cpp-precomp --sysroot='$SDKROOT' -isystem $SDKROOT/usr/include -isystem $DEVROOT/usr/include -isystem /opt/iphone-$SDKVER/include -isystem /usr/local/iphone-$SDKVER/include"
export LDFLAGS="-arch armv6 --sysroot='$SDKROOT' -L$SDKROOT/usr/lib -L$DEVROOT/usr/lib -L/opt/iphone-$SDKVER/lib -L/usr/local/iphone-$SDKVER/lib"
export CPP="$DEVROOT/usr/bin/cpp-4.2"
export CC="$DEVROOT/usr/bin/gcc-4.2"
export CXX="$DEVROOT/usr/bin/g++-4.2"
export LD="$DEVROOT/usr/bin/ld"

if [ ! \( -d "$DEVROOT" \) ] ; then
   echo "The iPhone SDK could not be found. Folder \"$DEVROOT\" does not exist."
   exit 1
fi

if [ ! \( -d "$SDKROOT" \) ] ; then
   echo "The iPhone SDK could not be found. Folder \"$SDKROOT\" does not exist."
   exit 1
fi

./configure --prefix="$PREFIX" --build="i386-apple-darwin$BUILD_DARWIN_VER" --host="arm-apple-darwin9" --enable-static --disable-shared $@

In the "apr-1.3.8" folder, I am running "iphone3.1-configure --disable-dso", and am getting:

checking build system type... i386-apple-darwin10.0.0
checking host system type... arm-apple-darwin9
checking target system type... arm-apple-darwin9
Configuring APR library
Platform: arm-apple-darwin9
checking for working mkdir -p... yes
APR Version: 1.3.8
checking for chosen layout... apr
checking for arm-apple-darwin9-gcc... /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc-4.2
checking for C compiler default output file name... a.out
checking whether the C compiler works... yes
checking whether we are cross compiling... yes
checking for suffix of executables... 
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc-4.2 accepts -g... yes
checking for /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc-4.2 option to accept ISO C89... unsupported
Applying APR hints file rules for arm-apple-darwin9
  adding "-DDARWIN" to CPPFLAGS
  adding "-DSIGPROCMASK_SETS_THREAD_MASK" to CPPFLAGS
  setting apr_posixsem_is_global to "yes"
  setting ac_cv_func_kqueue to "no"
  setting ac_cv_func_poll to "no"
(Default will be unix)
checking whether make sets $(MAKE)... yes
checking how to run the C preprocessor... /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/cpp-4.2
configure: error: in `/Users/michaelsafyan/Downloads/apr-1.3.8':
configure: error: C preprocessor "/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/cpp-4.2" fails sanity check
See `config.log' for more details.

The relevant part of "config.log" is:

configure:7710: checking how to run the C preprocessor
configure:7828: result: /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/cpp-4.2
configure:7857: /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/cpp-4.2 -std=c99 -arch armv6 -pipe -no-cpp-precomp --sysroot='/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS3.1.sdk' -isystem /Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS3.1.sdk/usr/include -isystem /Developer/Platforms/iPhoneOS.platform/Developer/usr/include -isystem /opt/iphone-3.1/include -isystem /usr/local/iphone-3.1/include -DDARWIN -DSIGPROCMASK_SETS_THREAD_MASK conftest.c
cpp-4.2: error trying to exec 'cc1': execvp: No such file or directory
configure:7864: $? = 1
configure: failed program was:
| /* confdefs.h.  */
| #define PACKAGE_NAME ""
| #define PACKAGE_TARNAME ""
| #define PACKAGE_VERSION ""
| #define PACKAGE_STRING ""
| #define PACKAGE_BUGREPORT ""
| /* end confdefs.h.  */
| #ifdef __STDC__
| # include 
| #else
| # include 
| #endif
|            Syntax error
configure:7857: /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/cpp-4.2 -std=c99 -arch armv6 -pipe -no-cpp-precomp --sysroot='/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS3.1.sdk' -isystem /Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS3.1.sdk/usr/include -isystem /Developer/Platforms/iPhoneOS.platform/Developer/usr/include -isystem /opt/iphone-3.1/include -isystem /usr/local/iphone-3.1/include -DDARWIN -DSIGPROCMASK_SETS_THREAD_MASK conftest.c
cpp-4.2: error trying to exec 'cc1': execvp: No such file or directory
configure:7864: $? = 1
configure: failed program was:
| /* confdefs.h.  */
| #define PACKAGE_NAME ""
| #define PACKAGE_TARNAME ""
| #define PACKAGE_VERSION ""
| #define PACKAGE_STRING ""
| #define PACKAGE_BUGREPORT ""
| /* end confdefs.h.  */
| #ifdef __STDC__
| # include 
| #else
| # include 
| #endif
|            Syntax error
configure:7926: error: in `/Users/michaelsafyan/Downloads/apr-1.3.8':
configure:7929: error: C preprocessor "/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/cpp-4.2" fails sanity check
See `config.log' for more details.

Question

How do I fix the "iphone3.1-configure" script? Thanks.

Toucan

Answer 1

Ok. This still doesn't build, but it gets much further...

1. The C preprocessor cannot take an architecture.
2. The C preprocessor does not accept --sysroot or -isystem (just use '-I').
3. Use "cpp" instead of "cpp-4.2" (the 4.2 version is defective, and since it is the preprocessor, it doesn't matter which version you use, anyway, so you might as well use the one that works.)

The updated version of the iphone3.1-configure script is:

#! /bin/bash

#
# Program  : iphone3.1-configure
# Authors  : Michael Aaron Safyan ([email protected])
# Synopsis :
#            This program runs the "configure" script generated by the
#            GNU Autotools in order to cross-compile thirdparty libraries
#            for the iPhone 3.1 SDK. Run this script while in a directory
#            containing an autotools "configure" script. Once you run this,
#            you can use "make" and "sudo make install" to build the library.
#            An install prefix of "/opt/iphone-3.1/" is used.
#

unset CPATH
unset C_INCLUDE_PATH
unset CPLUS_INCLUDE_PATH
unset OBJC_INCLUDE_PATH
unset LIBS
unset DYLD_FALLBACK_LIBRARY_PATH
unset DYLD_FALLBACK_FRAMEWORK_PATH

export BUILD_DARWIN_VER=`uname -r`
export SDKVER="3.1"
export DEVROOT="/Developer/Platforms/iPhoneOS.platform/Developer"
export SDKROOT="$DEVROOT/SDKs/iPhoneOS$SDKVER.sdk"
export PKG_CONFIG_PATH=/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS$SDKVER.sdk/usr/lib/pkgconfig:/Developer/Platforms/iPhoneOS.platform/Developer/usr/lib/pkgconfig:/opt/iphone-$SDKVER/lib/pkgconfig:/usr/local/iphone-$SDKVER/lib/pkgconfig
export PREFIX="/opt/iphone-$SDKVER"
export AS="$DEVROOT/usr/bin/as"
export ASCPP="$DEVROOT/usr/bin/as"
export AR="$DEVROOT/usr/bin/ar"
export RANLIB="$DEVROOT/usr/bin/ranlib"
export CPPFLAGS="-pipe -no-cpp-precomp -I$SDKROOT/usr/lib/gcc/arm-apple-darwin9/4.2.1/include/ -I$SDKROOT/usr/include -I$DEVROOT/usr/include -I/opt/iphone-$SDKVER/include -I/usr/local/iphone-$SDKVER/include"
export CFLAGS="-std=c99 -arch armv6 -pipe -no-cpp-precomp --sysroot='$SDKROOT' -isystem $SDKROOT/usr/lib/gcc/arm-apple-darwin9/4.2.1/include/ -isystem $SDKROOT/usr/include -isystem $DEVROOT/usr/include -isystem /opt/iphone-$SDKVER/include -isystem /usr/local/iphone-$SDKVER/include"
export CXXFLAGS="-std=c99 -arch armv6 -pipe -no-cpp-precomp --sysroot='$SDKROOT' -isystem $SDKROOT/usr/lib/gcc/arm-apple-darwin9/4.2.1/include/ -isystem $SDKROOT/usr/include -isystem $DEVROOT/usr/include -isystem /opt/iphone-$SDKVER/include -isystem /usr/local/iphone-$SDKVER/include"
export LDFLAGS="-arch armv6 --sysroot='$SDKROOT' -L$SDKROOT/usr/lib -L$DEVROOT/usr/lib -L/opt/iphone-$SDKVER/lib -L/usr/local/iphone-$SDKVER/lib"
export CPP="$DEVROOT/usr/bin/cpp"
export CXXCPP="$DEVROOT/usr/bin/cpp"
export CC="$DEVROOT/usr/bin/gcc-4.2"
export CXX="$DEVROOT/usr/bin/g++-4.2"
export LD="$DEVROOT/usr/bin/ld"
export STRIP="$DEVROOT/usr/bin/strip"

if [ ! \( -d "$DEVROOT" \) ] ; then
   echo "The iPhone SDK could not be found. Folder \"$DEVROOT\" does not exist."
   exit 1
fi

if [ ! \( -d "$SDKROOT" \) ] ; then
   echo "The iPhone SDK could not be found. Folder \"$SDKROOT\" does not exist."
   exit 1
fi

./configure --prefix="$PREFIX" --build="i386-apple-darwin$BUILD_DARWIN_VER" --host="arm-apple-darwin9" --enable-static --disable-shared ac_cv_file__dev_zero=no ac_cv_func_setpgrp_void=yes $@

Also, I am invoking with "--enable-threads --disable-dso", not just "--disable-dso". This still doesn't work... it is failing with:

checking for PTHREAD_PROCESS_SHARED in pthread.h... yes
checking for pthread_mutexattr_setpshared... yes
checking for working PROCESS_SHARED locks... configure: error: in `/Users/michaelsafyan/Downloads/apr-1.3.8':
configure: error: cannot run test program while cross compiling
See `config.log' for more details.

However, this may be a problem with APR's specific tests. I am posting a followup question at the link.

Edit

I have provided a more complete solution at Cross-compiling the Apache Portable Runtime for the iPhone.

Toucan

The 'Cross-compiling the Apache Portable Runtime for the iPhone' link is broken. Do you have an updated link? – Shela

That page was removed. Here's the author's explanation. – Bifoliolate

Answer 2

Thank you for your script. It did help me a lot. Though I had to make few changes so that the architecture of my built lib is arm and not i386.

First, I had to change the compiler:

# export CC="$DEVROOT/usr/bin/gcc-4.2"
export CC="$DEVROOT/usr/bin/arm-apple-darwin10-gcc-4.2.1"

Then I removed the -arch armv6 option, as this compiler doesn't understand it, from CFLAGS, CXXFLAGS, LDFLAGS

Updated the SDKVER and gcc version and it worked!

Vtol