Re: dwarf2 unwind info check broken

[Andreas Jaeger <aj@suse.de>]

Andreas Jaeger <aj@suse.de> writes:

> Andreas Jaeger <aj@suse.de> writes:
>
>> With current binutils and both gcc 2.95.3 and GCC 3.2 CVS on
>> i686-linux-gnu I now get:
>>
>> checking for DWARF2 unwind info support... (cached) no
>>
>> The test program from configure:
>> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> static char __EH_FRAME_BEGIN__[];
>
> I figured out the problem: the []; gets removed by autoconf - but my
> autoconf version didn't remove it. :-(

But that's not the whole story, something is still broken for me:

arthur:~/tmp:[1]$ /opt/gcc/3.2-devel/bin/gcc -DCHECK__register_frame_info -nostdlib -nostartfiles dwarf-test.c -o conftest -lgcc
dwarf-test.c: In function `abort':
dwarf-test.c:22: warning: `noreturn' function does return
/tmp/ccomS4ZM.o: In function `_start':
/tmp/ccomS4ZM.o(.text+0x11): undefined reference to `__register_frame_info'
/tmp/ccomS4ZM.o(.text+0x20): undefined reference to `__deregister_frame_info'
collect2: ld returned 1 exit status
arthur:~/tmp:[1]$ /opt/gcc/3.2-devel/bin/gcc -DCHECK__register_frame -nostdlib -nostartfiles dwarf-test.c -o conftest -lgcc
dwarf-test.c: In function `abort':
dwarf-test.c:22: warning: `noreturn' function does return
/tmp/ccQkgVW6.o: In function `_start':
/tmp/ccQkgVW6.o(.text+0x11): undefined reference to `__register_frame'
/tmp/ccQkgVW6.o(.text+0x20): undefined reference to `__deregister_frame'
collect2: ld returned 1 exit status

But adding -lgcc_s fixes the problem:

arthur:~/tmp:[1]$ /opt/gcc/3.2-devel/bin/gcc -DCHECK__register_frame -nostdlib -nostartfiles dwarf-test.c -o conftest -lgcc -lgcc_s
dwarf-test.c: In function `abort':
dwarf-test.c:22: warning: `noreturn' function does return
arthur:~/tmp:[0]$ /opt/gcc/3.2-devel/bin/gcc -DCHECK__register_frame_info -nostdlib -nostartfiles dwarf-test.c -o conftest -lgcc -lgcc_s
dwarf-test.c: In function `abort':
dwarf-test.c:22: warning: `noreturn' function does return

So, how can we fix that configure test - and do we need to add -lgcc_s
for sln?

Sorry, I'm a bit confused about this stuff...

Andreas
-- 
 Andreas Jaeger
  SuSE Labs aj@suse.de
   private aj@arthur.inka.de
    http://www.suse.de/~aj