Re: static linking

[Daniel Andrzejewski <andrzeje at cs dot utk dot edu>]

David Daney wrote:
> Daniel Andrzejewski wrote:
> > Hi all,
> >
> > I have a problem with gcj. I have read couple threads here, but I 
> > still have no idea how to fix my problem. Usually people say that this 
> > is hard but doable, but they don't give much directions.
> >
> > I'm trying to do it for a system where there's no shared libraries, so 
> > I must not even dynamically link libc.
>
> One might ask the question: Why?

Don't laugh, but I'm going to run it on a super computer (Cray XT), where on the compute nodes 
there's no shared libraries.

> > I successfully build gcc 4.3.0 with --disable-shared option. I can 
> > successfully compile a java program, but the executable is still 
> > dynamically linked.
> >
> > /scratch/daniel> ldd ./HelloWorld
> >         libz.so.1 => /lib64/libz.so.1 (0x00002adcd28dd000)
> >         libpthread.so.0 => /lib64/tls/libpthread.so.0 
> > (0x00002adcd29f0000)
> >         libc.so.6 => /lib64/tls/libc.so.6 (0x00002adcd2b04000)
> >         libm.so.6 => /lib64/tls/libm.so.6 (0x00002adcd2d26000)
> >         libdl.so.2 => /lib64/libdl.so.2 (0x00002adcd2e7d000)
> >         librt.so.1 => /lib64/tls/librt.so.1 (0x00002adcd2f80000)
> >         /lib64/ld-linux-x86-64.so.2 => /lib64/ld-linux-x86-64.so.2 
> > (0x00002adcd27c6000)
> >
> > When I use -static flag while compiling I get some warnings, but the 
> > executable gets compiled.
> >
> > /scratch/daniel> gcj --main=HelloWorld -o HelloWorld -static 
> > HelloWorld.java
> > ...
> > warnings
> > ...
>
> Do you know a priori that the content of the warnings is not relevant to 
> this problem?  If not, please include them.

I just thought it would mess up the message. But here you go:

/sw/xt/gcc/4.3.0/lib64/../lib64/libgcj.a(ltdl.o)(.text+0x341a): In function `sys_dl_open':
../../../../gcc/libjava/libltdl/ltdl.c:1114: warning: Using 'dlopen' in statically linked 
applications requires at runtime the shared libraries from the glibc version used for linking
/sw/xt/gcc/4.3.0/lib64/../lib64/libgcj.a(natSystemProperties.o)(.text+0x7b7): In function `hidden 
alias for void gnu::classpath::SystemProperties::insertSystemProperties(java::util::Properties*)':
../../../gcc/libjava/gnu/classpath/natSystemProperties.cc:97: warning: Using 'getpwuid_r' in 
statically linked applications requires at runtime the shared libraries from the glibc version used 
for linking
/sw/xt/gcc/4.3.0/lib64/../lib64/libgcj.a(natVMInetAddress.o)(.text+0x3bf): In function `hidden alias 
for java::lang::String* java::net::VMInetAddress::getHostByAddr(JArray<char>*)':
java/net/natVMInetAddress.cc:148: warning: Using 'gethostbyaddr_r' in statically linked applications 
requires at runtime the shared libraries from the glibc version used for linking
/sw/xt/gcc/4.3.0/lib64/../lib64/libgcj.a(natVMInetAddress.o)(.text+0x201): In function `hidden alias 
for JArray<JArray<char>*>* java::net::VMInetAddress::getHostByName(java::lang::String*)':
java/net/natVMInetAddress.cc:218: warning: Using 'gethostbyname_r' in statically linked applications 
requires at runtime the shared libraries from the glibc version used for linking



> First start with only -static-libgcj to isolate C library problems from 
> libgcj problems.

If I do -static-libgcj instead of -static it compiles fine and runs perfectly, but it is dynamically 
linked then.

> > /scratch/daniel> file HelloWorld
> > HelloWorld: ELF 64-bit LSB executable, AMD x86-64, version 1 (SYSV), 
> > for GNU/Linux 2.4.1, statically linked, not stripped
> >
> >
> > And the problem is at the runtime:
> >
> > /scratch/daniel> ./HelloWorld
> > Aborted
>
> That is not too helpful.  You need to run the thing under gdb and at a 
> minimum see where it is failing (put a breakpoint on abort()).

/scratch/daniel> gdb HelloWorld
GNU gdb 6.3
Copyright 2004 Free Software Foundation, Inc.
...

(gdb) break 12
Breakpoint 1 at 0x400324: file /tmp/cc0TNqNE.i, line 12.
(gdb) run
Starting program: /scratch/daniel/HelloWorld

Program received signal SIGSEGV, Segmentation fault.
0x0000000000000000 in ?? ()
(gdb) break 11
Breakpoint 2 at 0x40030e: file /tmp/cc0TNqNE.i, line 11.
(gdb) run
The program being debugged has been started already.
Start it from the beginning? (y or n) y
Starting program: /scratch/daniel/HelloWorld

Breakpoint 2, main (argc=1, argv=0x7fff29a68c38) at /tmp/cc0TNqNE.i:11
11      /tmp/cc0TNqNE.i: No such file or directory.
        in /tmp/cc0TNqNE.i
(gdb) n

Program received signal SIGSEGV, Segmentation fault.
0x0000000000000000 in ?? ()
(gdb)


It's not clear to me why the temp file is missing.

> > Has anyone solved this issue yet?
>
> I have not used a static glibc, but I successfully do static linking of 
> libgcj.  Most problems come down to missing classes due to the linker 
> not linking classes that are only referred to dynamically.
>
> I put the following into my main code to force some necessary classes to 
> be linked:
>
> extern int _ZN3gnu4java6locale8Calendar6class$E;
> int *dummy1 = &_ZN3gnu4java6locale8Calendar6class$E;
>
> extern int _ZN3gnu4java6locale17LocaleInformation6class$E;
> int *dummy2 = &_ZN3gnu4java6locale17LocaleInformation6class$E;
>
> extern int _ZN3gnu3gcj7convert12Output_ASCII6class$E;
> int *dummy3 = &_ZN3gnu3gcj7convert12Output_ASCII6class$E;
>
> extern int _ZN3gnu3gcj7convert11Output_UTF86class$E;
> int *dummy5 = &_ZN3gnu3gcj7convert11Output_UTF86class$E;
>
> #ifdef STATIC_LIBGCJ_4_3
> extern int _ZGr32_java$Sutil$Siso4217$_properties;
> int *dummy6 = &_ZGr32_java$Sutil$Siso4217$_properties;
>
> extern int _ZN3gnu3xml8aelfred29XmlParser6class$E;
> int *dummy7 = &_ZN3gnu3xml8aelfred29XmlParser6class$E;
>
> #endif
>
>
> Note that either fewer or more classes may be needed by your application.

Thanks,

Daniel

--
Daniel Andrzejewski
student IT Administrator
Elec Engr & Comp Science
University of Tennessee
(865) 974 - 4388 (work)

"Investment in knowledge always pays the best interest" Benjamin Franklin
--