gdb darwin target on Linux host?

gdb darwin target on Linux host?

[Peter Steiner]

Hi

I try to compile a darwin-target gdb running on a Linux host:

./configure --prefix=/usr/local/gdb --target=x86_64-darwin

this works up to the end of configure & make however does NOT generate a
gdb binary! After make install the bin directory is empty and NO gdb
binary has been linked at all.

if I do:

./configure --prefix=/usr/local/gdb --target=i386-darwin

this creates a gdb binary however it cannot read 64bit binaries from
darwin. Any idea what is wrong?

Thanks.

Re: gdb darwin target on Linux host?

[Tristan Gingold]

On Oct 20, 2010, at 3:52 PM, Peter Steiner wrote:

> Hi
> 
> I try to compile a darwin-target gdb running on a Linux host:
> 
> ./configure --prefix=/usr/local/gdb --target=x86_64-darwin
> 
> this works up to the end of configure & make however does NOT generate a
> gdb binary! After make install the bin directory is empty and NO gdb
> binary has been linked at all.
> 
> if I do:
> 
> ./configure --prefix=/usr/local/gdb --target=i386-darwin
> 
> this creates a gdb binary however it cannot read 64bit binaries from
> darwin. Any idea what is wrong?

Could you post the log messages ?  I suppose that if no binary is built, then an error has occurred.

Not sure why you try to build such a tool, as it would be basically useless to debug.

Re: gdb darwin target on Linux host?

[Pedro Alves]

On Wednesday 20 October 2010 15:20:49, Tristan Gingold wrote:
> 
> On Oct 20, 2010, at 3:52 PM, Peter Steiner wrote:
> 
> > Hi
> > 
> > I try to compile a darwin-target gdb running on a Linux host:
> > 
> > ./configure --prefix=/usr/local/gdb --target=x86_64-darwin
> > 
> > this works up to the end of configure & make however does NOT generate a
> > gdb binary! After make install the bin directory is empty and NO gdb
> > binary has been linked at all.
> > 
> > if I do:
> > 
> > ./configure --prefix=/usr/local/gdb --target=i386-darwin
> > 
> > this creates a gdb binary however it cannot read 64bit binaries from
> > darwin. Any idea what is wrong?
> 
> Could you post the log messages ?  I suppose that if no binary is built, then an error has occurred.
> 
> Not sure why you try to build such a tool, as it would be basically useless to debug.
> 
> 

Apparently, the top-level configure is finicky about darwin versions:

  i[[3456789]]86-*-darwin*)
    noconfigdirs="$noconfigdirs ld gprof"
    noconfigdirs="$noconfigdirs sim target-rda"
    ;;
  x86_64-*-darwin[[912]]*)
    noconfigdirs="$noconfigdirs ld gas gprof"
    noconfigdirs="$noconfigdirs sim target-rda"
    ;;
  *-*-darwin*)
    noconfigdirs="$noconfigdirs ld gas gdb gprof"
                                       ^^^
    noconfigdirs="$noconfigdirs sim target-rda"
    noconfigdirs="$noconfigdirs ${libgcj}"
    ;;


Something like "--target=x86_64-darwin10" instead works, and
I suppose "--target=i386-darwin --enable-64-bit-bfd" would
solve the OPs second attempt.

-- 
Pedro Alves

Re: gdb darwin target on Linux host?

[Tristan Gingold]

On Oct 20, 2010, at 4:26 PM, Pedro Alves wrote:

> Apparently, the top-level configure is finicky about darwin versions:
> 
>  i[[3456789]]86-*-darwin*)
>    noconfigdirs="$noconfigdirs ld gprof"
>    noconfigdirs="$noconfigdirs sim target-rda"
>    ;;
>  x86_64-*-darwin[[912]]*)
>    noconfigdirs="$noconfigdirs ld gas gprof"
>    noconfigdirs="$noconfigdirs sim target-rda"
>    ;;
>  *-*-darwin*)
>    noconfigdirs="$noconfigdirs ld gas gdb gprof"
>                                       ^^^
>    noconfigdirs="$noconfigdirs sim target-rda"
>    noconfigdirs="$noconfigdirs ${libgcj}"
>    ;;
> 
> 
> Something like "--target=x86_64-darwin10" instead works, and
> I suppose "--target=i386-darwin --enable-64-bit-bfd" would
> solve the OPs second attempt.

Ah, ah.  Maybe you should remove the '[[912]]' part ?

Re: gdb darwin target on Linux host?

[Pedro Alves]

On Wednesday 20 October 2010 15:41:32, Tristan Gingold wrote:
> 
> On Oct 20, 2010, at 4:26 PM, Pedro Alves wrote:
> 
> > Apparently, the top-level configure is finicky about darwin versions:
> > 
> >  i[[3456789]]86-*-darwin*)
> >    noconfigdirs="$noconfigdirs ld gprof"
> >    noconfigdirs="$noconfigdirs sim target-rda"
> >    ;;
> >  x86_64-*-darwin[[912]]*)
> >    noconfigdirs="$noconfigdirs ld gas gprof"
> >    noconfigdirs="$noconfigdirs sim target-rda"
> >    ;;
> >  *-*-darwin*)
> >    noconfigdirs="$noconfigdirs ld gas gdb gprof"
> >                                       ^^^
> >    noconfigdirs="$noconfigdirs sim target-rda"
> >    noconfigdirs="$noconfigdirs ${libgcj}"
> >    ;;
> > 
> > 
> > Something like "--target=x86_64-darwin10" instead works, and
> > I suppose "--target=i386-darwin --enable-64-bit-bfd" would
> > solve the OPs second attempt.
> 
> Ah, ah.  Maybe you should remove the '[[912]]' part ?

I believe so, but I have zero powers over the top level, so
someone interested in darwin needs to step up for that.  :-)

-- 
Pedro Alves

Re: gdb darwin target on Linux host?

[Nathan Froyd]

On Wed, Oct 20, 2010 at 03:50:25PM +0100, Pedro Alves wrote:
> On Wednesday 20 October 2010 15:41:32, Tristan Gingold wrote:
> > On Oct 20, 2010, at 4:26 PM, Pedro Alves wrote:
> > >  x86_64-*-darwin[[912]]*)
> > >    noconfigdirs="$noconfigdirs ld gas gprof"
> > >    noconfigdirs="$noconfigdirs sim target-rda"
> > >    ;;
> > >  *-*-darwin*)
> > >    noconfigdirs="$noconfigdirs ld gas gdb gprof"
> > >                                       ^^^
> > >    noconfigdirs="$noconfigdirs sim target-rda"
> > >    noconfigdirs="$noconfigdirs ${libgcj}"
> > >    ;;
> > > 
> > > 
> > > Something like "--target=x86_64-darwin10" instead works, and
> > > I suppose "--target=i386-darwin --enable-64-bit-bfd" would
> > > solve the OPs second attempt.
> > 
> > Ah, ah.  Maybe you should remove the '[[912]]' part ?
> 
> I believe so, but I have zero powers over the top level, so
> someone interested in darwin needs to step up for that.  :-)

I think the decision is deliberate, as x86_64-darwin8 is not a valid
target.

-Nathan

Re: gdb darwin target on Linux host?

[Pedro Alves]

On Wednesday 20 October 2010 15:52:47, Nathan Froyd wrote:

> I think the decision is deliberate, as x86_64-darwin8 is not a valid
> target.

That sounds like gcc-isms escaping into the top-level.
config.sub expands x86_64-darwin to ... x86_64-pc-darwin, and
neither bfd nor gdb (at least) need to distinguish between darwin
revisions.  IMO, if x86_64-darwin8 should be verbotten, there should
be an explicit "x86_64-*-darwin8*" or some such forcing an error.

-- 
Pedro Alves

Re: gdb darwin target on Linux host?

[Peter Steiner]

made a cross-check o a native darwin box, and I get the "not recognized"
error too:

root# gdb/gdb /bin/ls
GNU gdb (GDB) 7.2
Copyright (C) 2010 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later
<http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show
copying"
and "show warranty" for details.
This GDB was configured as "x86_64-apple-darwin10.0.0".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
"/bin/ls": not in executable format: File format not recognized
					^^^^^^^

So, I assume your packaged libbfd cannot handle these binaries at all?
(from your gdb-7.2.tar.bz2)

Re: gdb darwin target on Linux host?

[Peter Steiner]

On Wed, 2010-10-20 at 16:20 +0200, Tristan Gingold wrote:
> Could you post the log messages ?  I suppose that if no binary is
> built, then an error has occurred.
> 
> Not sure why you try to build such a tool, as it would be basically
> useless to debug.
> 
Hi

found the bug - there must be some typo/bug in your build system as it
does not build the gdb/ directory at all with --target=x86_64-darwin!

I had to run configure in topdir first then after it finishes cd gdb,
then rerun same configure (--target=x86_64-darwin) in gdb dir, make,
cd .. && make install.

This worked and gives me:

l /usr/local/gdb/bin/
total 44032
drwxr-xr-x 2 root root     4096 2010-10-20 16:22 ./
drwxr-xr-x 6 root root     4096 2010-10-20 16:05 ../
-rwxr-xr-x 1 root root 17567402 2010-10-20 16:22
x86_64-apple-darwin-gdb*
-rwxr-xr-x 1 root root 17567431 2010-10-20 16:22
x86_64-apple-darwin-gdbtui*

BUT, there is another issue now. The so generated
x86_64-apple-darwin-gdb* does not recognize 64bit binaries:

(e.g. /home/exchange/ls is the binary I want to debug)

/usr/local/gdb/bin/x86_64-apple-darwin-gdb /home/exchange/ls
 
GNU gdb (GDB) 7.2
Copyright (C) 2010 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later
<http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show
copying"
and "show warranty" for details.
This GDB was configured as "--host= --target=x86_64-apple-darwin".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
"/home/exchange/ls": not in executable format: File format not
recognized
Setting up the environment for debugging gdb.

WHY it says:

"/home/exchange/ls": not in executable format: File format not
recognized

?

as I built for the darwin target?

file /home/exchange/ls
/home/exchange/ls: Mach-O fat file with 2 architectures

Re: gdb darwin target on Linux host?

[Tristan Gingold]

On Oct 20, 2010, at 4:42 PM, Peter Steiner wrote:

> On Wed, 2010-10-20 at 16:20 +0200, Tristan Gingold wrote:
>> Could you post the log messages ?  I suppose that if no binary is
>> built, then an error has occurred.
>> 
>> Not sure why you try to build such a tool, as it would be basically
>> useless to debug.

> "/home/exchange/ls": not in executable format: File format not
> recognized
> Setting up the environment for debugging gdb.
> 
> WHY it says:
> 
> "/home/exchange/ls": not in executable format: File format not
> recognized
> 
> ?
> 
> as I built for the darwin target?

> file /home/exchange/ls
> /home/exchange/ls: Mach-O fat file with 2 architectures

You can't debug fat binaries.  You have to extract the executable you really want to debug.

Re: gdb darwin target on Linux host?

[Peter Steiner]

> > file /home/exchange/ls
> > /home/exchange/ls: Mach-O fat file with 2 architectures
> 
> You can't debug fat binaries.  You have to extract the executable you really want to debug.
> 

ok - but the packaged Apple darwin gdb (shipped with my install) CAN
read the native binaries. So, what is the difference? Another/patched
libbfd used by Apple?

(e.g. http://www.opensource.apple.com/tarballs/gdb/gdb-1469.tar.gz
gdb version is 6.3.50.20050815-cvs)

however I do not want to debug natively (or my question here would be
pointless), I want to cross-debug using a Linux host.

Re: gdb darwin target on Linux host?

[Stan Shebs]

  On 10/20/10 8:24 AM, Peter Steiner wrote:
> ok - but the packaged Apple darwin gdb (shipped with my install) CAN
> read the native binaries. So, what is the difference? Another/patched
> libbfd used by Apple?
>
> (e.g. http://www.opensource.apple.com/tarballs/gdb/gdb-1469.tar.gz
> gdb version is 6.3.50.20050815-cvs)

"Patched" is, shall we say, an understatement. :-)

> however I do not want to debug natively (or my question here would be
> pointless), I want to cross-debug using a Linux host.

So, uh, once you get the executable read in, how exactly do you expect 
to remote-control execution from Linux-land?  Is there a Darwin 
GDBserver or equivalent that I don't know of?  There is a kernel 
debugging setup, but it's not useful for apps.

Stan

Re: gdb darwin target on Linux host?

[Tristan Gingold]

On Oct 20, 2010, at 7:12 PM, Stan Shebs wrote:
> 
>> however I do not want to debug natively (or my question here would be
>> pointless), I want to cross-debug using a Linux host.
> 
> So, uh, once you get the executable read in, how exactly do you expect to remote-control execution from Linux-land?  Is there a Darwin GDBserver or equivalent that I don't know of? 

As far as I know, no.

Tristan.

Re: gdb darwin target on Linux host?

[Peter Steiner]

> > file /home/exchange/ls
> > /home/exchange/ls: Mach-O fat file with 2 architectures
> 
> You can't debug fat binaries.  You have to extract the executable you really want to debug.
> 

tried this - no luck at all!

lipo -extract x86_64 /bin/ls -output ls.64
lipo -extract i386 /bin/ls -output ls.32

gdb-7.2 root# ./gdb/gdb /opt/src/ls.64 
GNU gdb (GDB) 7.2
Copyright (C) 2010 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later
<http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show
copying"
and "show warranty" for details.
This GDB was configured as "x86_64-apple-darwin10.0.0".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
"/opt/src/ls.64": not in executable format: File format not recognized

gdb-7.2 root# ./gdb/gdb /opt/src/ls.32 
GNU gdb (GDB) 7.2
Copyright (C) 2010 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later
<http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show
copying"
and "show warranty" for details.
This GDB was configured as "x86_64-apple-darwin10.0.0".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
"/opt/src/ls.32": not in executable format: File format not recognized

(this is all native darwin box)

Re: gdb darwin target on Linux host?

[Paul Starzetz]

On Wed, 2010-10-20 at 17:35 +0200, Peter Steiner wrote:
> > > file /home/exchange/ls
> > > /home/exchange/ls: Mach-O fat file with 2 architectures
> > 
> > You can't debug fat binaries.  You have to extract the executable you really want to debug.
> > 
> 
> tried this - no luck at all!
> 
> lipo -extract x86_64 /bin/ls -output ls.64
> lipo -extract i386 /bin/ls -output ls.32

ok ok I see my error... I must use -thin:

lipo -thin x86_64 /bin/ls -output ls.64

now I can load it into native box gdb7.2:

gdb-7.2 root# ./gdb/gdb /opt/src/ls.64
GNU gdb (GDB) 7.2
Copyright (C) 2010 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later
<http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show
copying"
and "show warranty" for details.
This GDB was configured as "x86_64-apple-darwin10.0.0".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /opt/src/ls.64...(no debugging symbols
found)...done.


BUT: on a cross-gdb compiled on Linux host I get now another error
trying to read the "thinned" ls.64:

gdb-7.2/gdb
#  /usr/local/gdb/bin/x86_64-apple-darwin-gdb /home/exchange/ls.64
GNU gdb (GDB) 7.2
Copyright (C) 2010 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later
<http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show
copying"
and "show warranty" for details.
This GDB was configured as "--host= --target=x86_64-apple-darwin".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /home/exchange/ls.64...I'm sorry, Dave, I can't do
that.  Symbol format `mach-o-x86-64' unknown.
Setting up the environment for debugging gdb.

why is that? I compiled on native darwin and Linux from the same tarball
7.2.