Catching exceptions with objective-c in Linux

I have some sample code that doesn't run the way I think it should.

#import <Foundation/NSString.h>
#import <Foundation/NSException.h>
#import <Foundation/NSAutoreleasePool.h>
#import <std开发者_StackOverflow中文版io.h>

int main( int argc, const char *argv[] ) {
  NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

  @try {
    NSException *e = [NSException
      exceptionWithName: @"NSException"
                 reason: @"The level is below 0"
               userInfo: nil];
    @throw e;
  } @catch ( NSException *e ) {
    printf( "+%s: ", [[e name] UTF8String] );
  }

  [pool release];
}

I run it as following:

> gcc -g -c main.m -fconstant-string-class=NSConstantString -I/usr/include/GNUstep
> gcc main.o -lgnustep-base
> ./a.out

The result is:

Aborted

A little bit of playing with the GNU debugger showed me that the catch clause is never reached. It seems to work mac though.

Why do I not get into the catch clause?

The answers needed can be found in this mail thread: http://www.mail-archive.com/discuss-gnustep@gnu.org/msg11979.html

To get proper objective-c exception handling one might need to compile with the -fobjc-exceptions flag.

> gcc -g -c main.m -fconstant-string-class=NSConstantString -fobjc-exceptions -I/usr/include/GNUstep
> gcc main.o -lgnustep-base
> ./a.out