GNUstep under Ubuntu Linux

Objective-C under Ubuntu Linux

Compiling Everything from Scratch

The compilation instructions below are divided into two steps. The first step compiles the *base* (non-graphical) parts of GNUStep, including setting up the Objective-C compiler. The second step compiles the graphical parts of GNUStep. After installing everything below, you could install EtoileOS: see EtoileOS under Ubuntu Linux.

If you are using Ubuntu 12.04, your version of CMake and/or g++ may be too old to handle the newer versions of LLVM. See the bottom of this wiki page for instructions on how to get a newer version of CMake working.

Reference manuals for GNUStep, including available APIs, etc, are available at http://www.gnustep.org/developers/documentation.html

sudo apt-get install aptitude
# Dependencies
sudo aptitude -y install build-essential git subversion ninja cmake
# Dependencies for GNUStep Base
sudo aptitude -y install libffi-dev libxml2-dev libgnutls-dev libicu-dev 
# Dependencies for libdispatch
sudo aptitude -y install libblocksruntime-dev libkqueue-dev libpthread-workqueue-dev autoconf libtool

cd ~
git clone git://github.com/nickhutchinson/libdispatch.git
svn co http://svn.gna.org/svn/gnustep/modules/core
svn co http://svn.gna.org/svn/gnustep/libs/libobjc2/trunk libobjc2
svn co http://llvm.org/svn/llvm-project/llvm/trunk llvm
cd llvm/tools
svn co http://llvm.org/svn/llvm-project/cfe/trunk clang

cd ~/llvm
mkdir build
cd build
cmake ..
make -j8   # 8=your number of build CPUs

echo "export PATH=\$PATH:~/llvm/build/bin" >> ~/.bashrc
echo "export CC=clang"  >> ~/.bashrc
echo "export CXX=clang++" >> ~/.bashrc
source ~/.bashrc
clang -v
clang++ -v

cd ~/libobjc2
mkdir build
cd build
cmake ..
make -j8
sudo -E make install

cd ~/core/make
./configure --enable-debug-by-default --with-layout=gnustep --enable-objc-nonfragile-abi
make && sudo -E make install
echo ". /usr/GNUstep/System/Library/Makefiles/GNUstep.sh" >> ~/.bashrc
source ~/.bashrc

sudo /sbin/ldconfig

cd ~/core/base/
./configure
make -j8
sudo -E make install

cd ~/libdispatch
mkdir libdispatch-build && cd libdispatch-build
../configure
make
sudo make install
sudo ldconfig

# ----------------------------------------------------------------------------------------
# TEST COMPILING SOME CODE FROM THE INTERNET
# ----------------------------------------------------------------------------------------

You can compile the following code with:

clang `gnustep-config --objc-flags` `gnustep-config --objc-libs` -fobjc-runtime=gnustep -fblocks -fobjc-arc -lobjc  blocktest.m 

clang `gnustep-config --objc-flags` `gnustep-config --objc-libs` -fobjc-runtime=gnustep -fblocks -lobjc -ldispatch -lgnustep-base  Fraction.m helloGCD_objc.m



cat > blocktest.m << EOF
#include <stdio.h>

int main() {
    void (^hello)(void) = ^(void) {
        printf("Hello, block!\n");
    };
    hello();
    return 0;
}
EOF

cat > helloGCD_objc.m << EOF

#include <dispatch/dispatch.h>
#import <stdio.h>
#import "Fraction.h"

int main( int argc, const char *argv[] ) {
   dispatch_queue_t queue = dispatch_queue_create(NULL, NULL); 
   Fraction *frac = [[Fraction alloc] init];

   [frac setNumerator: 1];
   [frac setDenominator: 3];

   // print it
   dispatch_sync(queue, ^{
     printf( "The fraction is: " );
     [frac print];
     printf( "\n" );
   });
   dispatch_release(queue);

   return 0;
}

EOF

cat > Fraction.h << EOF

#import <Foundation/NSObject.h>

@interface Fraction: NSObject {
   int numerator;
   int denominator;
}

-(void) print;
-(void) setNumerator: (int) n;
-(void) setDenominator: (int) d;
-(int) numerator;
-(int) denominator;
@end

EOF


cat > Fraction.m << EOF
#import "Fraction.h"
#import <stdio.h>

@implementation Fraction
-(void) print {
   printf( "%i/%i", numerator, denominator );
}

-(void) setNumerator: (int) n {
   numerator = n;
}

-(void) setDenominator: (int) d {
   denominator = d;
}

-(int) denominator {
   return denominator;
}

-(int) numerator {
   return numerator;
}
@end

EOF


# ------------------------------------------------------
# STEP 2:  INSTALLING GUI AND BACK
# (i.e., if you're running Ubuntu Desktop)
# ------------------------------------------------------

sudo aptitude install -y libjpeg-dev libtiff-dev libffi-dev
sudo aptitude install -y libcairo-dev libx11-dev:i386 libxt-dev

cd ~/core/gui
./configure
make -j8
sudo -E make install

cd ~/core/back
./configure
make -j8
sudo -E make install

You can compile the following code with:

clang `gnustep-config --objc-flags` `gnustep-config --objc-libs`  -fobjc-runtime=gnustep -fblocks -lobjc -fobjc-arc -ldispatch -lgnustep-base -lgnustep-gui  guitest.m



cat > guitest.m << EOF
#import <AppKit/AppKit.h>

int main()
{
  NSApplication *app;  // Without these 2 lines, seg fault may occur
  app = [NSApplication sharedApplication];

  NSAlert * alert = [[NSAlert alloc] init];
  [alert setMessageText:@"Hello alert"];
  [alert addButtonWithTitle:@"All done"];
  int result = [alert runModal];
  if (result == NSAlertFirstButtonReturn) {
    NSLog(@"First button pressed");
  }
}
EOF

General Note: When compiling your own code, it is generally good to tell clang both the family and version of the runtime: -fobjc-runtime=gnustep-1.7 (The current version number can be had by looking at the latest ANNOUNCE filename in http://svn.gna.org/svn/gnustep/libs/libobjc2/trunk/ (e.g., ANNOUNCE.1.7))

Some other notes:

• We use clang and libobjc2 for all the new features like ARC, Blocks, etc.
• Tested on fresh installs of (and likely with a more completed installation of):
• Ubuntu 12.10 Server.
• Ubuntu 13.10 Desktop.
• Ubuntu 12.04 LTS Desktop, see bottom of the page for important info.

Ubuntu 12.04 Help

On Ubuntu 12.04, the default installed version of CMake is 2.8.7 but you need 2.8.8 or later to compile LLVM. And the default installed version of GCC and G++ is 4.6 but you need 4.8 or later to compile LLVM.

For CMake, the solution is to download and compile CMake yourself. Use the existing CMake 2.8.7 and then replace it:

1. Download the latest CMake version from the CMake web site (http://www.cmake.org/cmake/resources/software.html), and uncompress it in a folder.
2. Create a _build directory in the CMake sources folder.
3. From the _build directory, run the following commands to build and install CMake from sources:

cmake .. -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr
make
cpack -G DEB
sudo apt-get remove cmake cmake-data
sudo dpkg -i cmake*.deb

To get GCC and G++ 4.8, do the following:

sudo add-apt-repository ppa:ubuntu-toolchain-r/test
sudo apt-get update
sudo apt-get install gcc-4.8 g++-4.8
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.8 50
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.8 50

You should be good to go.