On Tue, Feb 17, 2009 at 6:16 AM, cnav <c...@talamasca.pl> wrote:
> Jacob Meuser wrote:
>>
>> On Tue, Feb 17, 2009 at 09:03:18AM +0100, cnav wrote:
>>>
>>> Jacob Meuser wrote:
>>>>
>>>> On Mon, Feb 16, 2009 at 09:06:25AM -0800, patrick keshishian wrote:
>>>>>
>>>>> man cc
>>>>> /-pthread
>>>>> nn
>>>>>
>>>>> -pthreads
>>>>> Add support for multithreading using the POSIX threads
>>>>> library. This option sets flags for both the
>>>>> preprocessor and linker. This option does not affect
>>>>> the thread safety of object code produced by the
>>>>> compiler or that of libraries supplied with it.
>>>>>
>>>> that doesn't answer the questions.
>>>>
>>>>> On Mon, Feb 16, 2009 at 5:32 AM, cnav <c...@talamasca.pl> wrote:
>>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> I just applied following patch:
>>>>>> http://cnav.pl/clamav-configure.patch
>>>>>>
>>>>>> to clamav sources. And after that libclamav seems to work with
>>>>>> pthreads.
>>>>>> ldd /usr/local/lib/libclamav.so.5.4
>>>>>> /usr/local/lib/libclamav.so.5.4:
>>>>>> Start End Type Open Ref GrpRef Name
>>>>>> 084ef000 28522000 dlib 1 0 0
>>>>>> /usr/local/lib/libclamav.so.5.4
>>>>>> 0d4b9000 2d4bd000 rlib 0 1 0
>>>>>> /usr/local/lib/libclamunrar_iface.so.5.4
>>>>>> 010a0000 210a5000 rlib 0 2 0
>>>>>> /usr/local/lib/libclamunrar.so.5.4
>>>>>> 06d89000 26d8d000 rlib 0 1 0 /usr/local/lib/libbz2.so.10.4
>>>>>> 091a8000 291af000 rlib 0 1 0
>>>>>> /usr/local/lib/libgmp.so.7.1
>>>>>> 0a04b000 2a12a000 rlib 0 1 0 /usr/local/lib/libiconv.so.5.0
>>>>>> 02484000 2248d000 rlib 0 1 0
>>>>>> /usr/lib/libpthread.so.11.0
>>>>>> 05a7c000 25a84000 rlib 0 3 0 /usr/lib/libz.so.4.1
>>>>>>
>>>>>> Manuals says to use -pthread.
>>>>>> http://www.openbsd.org/cgi-bin/man.cgi?query=pthreads&sektion=3
>>>>>>
>>>>>> My question are:
>>>>>> What is the difference between those two libs ?
>>>>>> And why with -lpthread it's working and without not?
>>>>
>>>> -pthread won't link libpthread into shared objects, while -lpthread
>>>> will. use -pthread when linking the executables that will load
>>>> libclamav.
>>>>
>>> Thanks,
>>>
>>> The only one reason why i did it, is that i want to use perl module
>>> mail-clamav witch is depending pthreads libraries.
>>>
>>> When i am compiling libclamav with -pthread instead of -lpthread:
>>> The following error exists:
>>>
>>> Mail-ClamAV-0.22# make test
>>> PERL_DL_NONLAZY=1 /usr/bin/perl "-MExtUtils::Command::MM" "-e"
>>> "test_harness(0, 'blib/lib', 'blib/arch')" t/*.t
>>> t/Mail-ClamAV..../usr/bin/perl:/usr/local/lib/libclamav.so.5.4:
>>> undefined symbol 'pthread_create'
>>> /usr/bin/perl:/usr/local/lib/libclamav.so.5.4: undefined symbol
>>> 'pthread_getspecific'
>>> /usr/bin/perl:/usr/local/lib/libclamav.so.5.4: undefined symbol
>>> 'pthread_key_delete'
>>> /usr/bin/perl:/usr/local/lib/libclamav.so.5.4: undefined symbol
>>> 'pthread_once'
>>> /usr/bin/perl:/usr/local/lib/libclamav.so.5.4: undefined symbol
>>> 'pthread_key_create'
>>> /usr/bin/perl:/usr/local/lib/libclamav.so.5.4: undefined symbol
>>> 'pthread_mutex_unlock'
>>> /usr/bin/perl:/usr/local/lib/libclamav.so.5.4: undefined symbol
>>> 'pthread_mutex_lock'
>>> /usr/bin/perl:/usr/local/lib/libclamav.so.5.4: undefined symbol
>>> 'pthread_join'
>>> /usr/bin/perl:/usr/local/lib/libclamav.so.5.4: undefined symbol
>>> 'pthread_setspecific'
>>>
>>> I am aware that you maybe not familiar with mail-clamav, but libclamav
>>> at least should work fine with pthreads (-pthread) correctly ?
>>
>> no, because libclmav is a shared object, so -pthread doesn't pull
>> in libpthread.
>>
>>> Please, if any of you can help me understand it, it will be much
>>> helpful. (Or at least can you give me some directions where to search to.)
>>
>> I *think* you need to change ClamAV.pm to have -pthread in LIBS like
>>
>> use Inline C => Config =>
>> VERSION => $VERSION,
>> PREFIX => 'clamav_perl',
>> NAME => "Maile::ClamAV",
>> LIBS => "-lclamav -pthread";
>>
>> but I honestly don't know much about how perl modules are supposed to
>> be built.
>>
>
> I've tried yours solution, and i stuck with similar problem:
> LIBS => "-lclamav -pthread";
> Gives me this error while creating Makefile.
> Unrecognized argument in LIBS ignored: '-pthread'
>
> And with:
> LIBS => "-lclamav -lpthread";
> Is going fine and working, at least now i don't need to modify libclamav.
> But still it's -lpthread
Yes. -pthread is a compiler option that tells it to include -Defines
etc during the preprocessor stage and the proper -libs (e.g.,
-lpthread) during linker stage. My original reply was meant to
indicate this, based on my understanding of what you were asking: what
is the difference between -pthread and -lpthread.
I don't know how the module you are trying to build is attempting to
be compiled and linked. But it seems (maybe) openbsd's gcc is doing
things a bit different.
Here is a quick and dirty example:
linux$ cc -pthread -c a.c
linux$ cc -pthread a.o -shared -o liba.so -v
Using built-in specs.
Target: i386-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man
--infodir=/usr/share/info --enable-shared --enable-threads=posix
--enable-checking=release --with-system-zlib --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-libgcj-multifile
--enable-languages=c,c++,objc,obj-c++,java,fortran,ada
--enable-java-awt=gtk --disable-dssi --enable-plugin
--with-java-home=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0/jre
--with-cpu=generic --host=i386-redhat-linux
Thread model: posix
gcc version 4.1.2 20070626 (Red Hat 4.1.2-14)
/usr/libexec/gcc/i386-redhat-linux/4.1.2/collect2 --eh-frame-hdr -m
elf_i386 --hash-style=gnu -shared -o liba.so
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../crti.o
/usr/lib/gcc/i386-redhat-linux/4.1.2/crtbeginS.o
-L/usr/lib/gcc/i386-redhat-linux/4.1.2
-L/usr/lib/gcc/i386-redhat-linux/4.1.2
-L/usr/lib/gcc/i386-redhat-linux/4.1.2/../../.. a.o -lgcc --as-needed
-lgcc_s --no-as-needed -lpthread -lc -lgcc --as-needed -lgcc_s
--no-as-needed /usr/lib/gcc/i386-redhat-linux/4.1.2/crtendS.o
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../crtn.o
linux$ ldd liba.so
linux-gate.so.1 => (0x0087c000)
libpthread.so.0 => /lib/libpthread.so.0 (0x0069d000)
libc.so.6 => /lib/libc.so.6 (0x00505000)
/lib/ld-linux.so.2 (0x00461000)
obsd$ cc -pthread -c a.c
obsd$ cc -pthread a.o -shared -o liba.so -v
Reading specs from /usr/lib/gcc-lib/powerpc-unknown-openbsd4.4/3.3.5/specs
Configured with:
Thread model: single
gcc version 3.3.5 (propolice)
ld --eh-frame-hdr -shared -o liba.so /usr/lib/crtbeginS.o
-L/usr/lib/gcc-lib/powerpc-unknown-openbsd4.4/3.3.5 a.o -lgcc -lgcc
/usr/lib/gcc-lib/powerpc-unknown-openbsd4.4/3.3.5/crtsavres.o
/usr/lib/crtendS.o
obsd$ ldd liba.so
liba.so:
Start End Type Open Ref GrpRef Name
314bc000 3151e000 dlib 1 0 0 /tmp/liba.so
Note the missing -lpthread in the linker argument list in obsd.
However, if we try to make an executable -lpthread is added to the
linker argument list.
obsd$ cc -pthread -c b.c
obsd$ cc -pthread b.o -L. -la -v
Reading specs from /usr/lib/gcc-lib/powerpc-unknown-openbsd4.4/3.3.5/specs
Configured with:
Thread model: single
gcc version 3.3.5 (propolice)
ld --eh-frame-hdr -dynamic-linker /usr/libexec/ld.so /usr/lib/crt0.o
/usr/lib/crtbegin.o -L.
-L/usr/lib/gcc-lib/powerpc-unknown-openbsd4.4/3.3.5 b.o -la -lgcc
-lpthread -lc -lgcc
/usr/lib/gcc-lib/powerpc-unknown-openbsd4.4/3.3.5/crtsavres.o
/usr/lib/crtend.o
obsd$ env LD_LIBRARY_PATH=. ldd a.out
a.out:
Start End Type Open Ref GrpRef Name
01800000 01862000 exe 1 0 0 a.out
30ccd000 30d2f000 rlib 0 1 0 ./liba.so
2208b000 2210a000 rlib 0 1 0 /usr/lib/libpthread.so.11.1
29430000 29569000 rlib 0 1 0 /usr/lib/libc.so.50.1
2d7e0000 2d7e0000 rtld 0 1 0 /usr/libexec/ld.so
There is obviously a difference in the two compiler versions and also
archs, but I'm not sure if that accounts for the missing -lpthread in
the linker stage when creating a .so.
--patrick
