JNI compilation/linking issues on an HP-UX IA64 using gcc

[nallamolu]

Hi World,

1.) Can anyone provide me with the command line arguments that would be required to compile and link JNI 'c' code in 64bit mode using gcc ?

Compiler: gcc-hppa64-4.3.1.depot
Java : jdk6_16002_pa.depot
OS : IA64 11.23

2.) What are the Options we need to set for
compiling the java code in 64 bit mode.

[Dennis Handly]

>Java: jdk6_16002_pa.depot, OS: IA64 11.23

(I'm not sure why you have "_pa" when you are on IPF?)

Basically you need to compile in 64 bit mode: -mlp64

And run java with -d64.

[nallamolu]

Hi World,

I have used jdk6_16002_ia.depot for IA64 not the PA_RISC jvm ( It was a typing mistake ).

I compiled the JNI 'c' code in 64bit mode using gcc options:

GCC Compiling options as
gcc -fPIC -mlp64 -D_REENTRANT

GCC Linking Options as
gcc -lc -shared

I invoked the 64 Bit JVM using
-d64

While compiling i got the error as

[jnicc] ** COMPILER: ld: Mismatched ABI for -lgcc_s, found /opt/hp-gcc-4.3.1/lib/gcc/ia64-hp-hpux11.23/4.3.1/../../../libgcc_s.so

[jnicc] ** COMPILER: Fatal error.

[jnicc] ** COMPILER: collect2: ld returned 1 exit status

Error while executing gcc -g -lc -shared -o /tmp/nalgo01/libStats.so /tmp/nalgo01/compiler/hpuxmonitor/java_interface.o


I would appreciate any help on this

Thanks in Advance
Gopinath

[Dennis Handly]

>gcc linking options as: gcc -lc -shared

You forgot the most important option, -mlp64. Also leave -lc off all link lines.

[nallamolu]

Hi Dennis,

As u have said i have used the gcc linking options as

GCC Linking Options as
gcc -mlp64 -shared

It got compiled sucessfully.

I used the generated .jar and .so files in my application and it produced the following error

java.lang.UnsatisfiedLinkError: Can't load library: /tmp/nalgo01/Probeing/libStats.so
java.lang.ClassLoader.loadLibrary(ClassLoader.java:1650)
java.lang.Runtime.load0(Runtime.java:770)
java.lang.System.load(System.java:1005)


I would appreciate any help on this

Thanks in Advance
Gopinath

[Dennis Handly]

>java.lang.UnsatisfiedLinkError: Can't load library: /tmp/nalgo01/Probeing/libStats.so

This isn't helpful, it should print the unsatisfied symbol.

Can you relink with -lc and retry? I don't think it will fix it but it will make the nm(1) list below smaller.

Can you provide:
nm -px /tmp/nalgo01/Probeing/libStats.so | grep " U "

[nallamolu]

Hi Dennis,

linked With out -lc option

$ nm -p -x libIntroscopeHPUXItanium64Stats.so | grep " U "

0x0000000000000000 U atoi
0x0000000000000000 U free
0x0000000000000000 U getpid
0x0000000000000000 U getppid
0x0000000000000000 U getrusage
0x0000000000000000 U malloc
0x0000000000000000 U pstat_getdynamic
0x0000000000000000 U pstat_getprocessor
0x0000000000000000 U sysconf


linked With -lc option

$ nm -p -x libIntroscopeHPUXItanium64Stats.so | grep " U "

0x0000000000000000 U atoi
0x0000000000000000 U free
0x0000000000000000 U getpid
0x0000000000000000 U getppid
0x0000000000000000 U getrusage
0x0000000000000000 U malloc
0x0000000000000000 U pstat_getdynamic
0x0000000000000000 U pstat_getprocessor
0x0000000000000000 U sysconf

Both are producing the same result.

Does i need to set any ld or shlib path

Thanks in Advance
Gopinath

[Dennis Handly]

>U atoi ...
>U sysconf

These all should be defined in libc.

>linked With -lc option

Oops, that's linked with -lc and -Wl,+vshlibunsats

(So, you don't need nm(1).)

>Do I need to set any ld or shlib path?

No. I don't know if using -Wl,-Bverbose may help?
Have you looked at the java JNI documentation to see if there are specific symbols that must be defined?

[nallamolu]

> Oops, that's linked with -lc and -Wl,+vshlibunsats

can u please explain what it means

1.) Does using these options in linking helps
-Wl,+vshlibunsats

> No. I don't know if using -Wl,-Bverbose may help?

shall i use these options -Wl,-Bverbose as linker arguments

> Have you looked at the java JNI documentation to see if there are specific symbols that must be defined?

specific symbol means.. what kind of symboles

I would appreciate any help on this

Thanks in Advance
Gopinath

[Dennis Handly]

>1.) Does using these options in linking help -Wl,+vshlibunsats

No. They just will list the symbols that aren't defined in your shlib. Which I assumed was the cause of your java UnsatisfiedLinkError.

>shall I use these options -Wl,-Bverbose as linker arguments?

Yes, that may cause dld.so to print more verbose errors.

>specific symbol means. what kind of symbols?

Specific names.

[Dennis Handly]

Here is the JNI documentation. You might try out the sample first:
http://docs.hp.com/en/JAVAPROGUIDE/JNI_java2.html#java_native_c

[nallamolu]

Hi Dennis,

I have gone through the link which u have send
> http://docs.hp.com/en/JAVAPROGUIDE/JNI_java2.html#java_native_c

In this link i found a statement which states as follows...
""
On Integrity, create the shared library using:

$ aCC -b -o libaCCImpl.so aCCImpl.o \
-lstd_v2 -lCsup -lunwind -lm

On Integrity, the -AA lib -lstd_v2 is necessary, otherwise, running the program will result in UnsatisfiedLinkErrors.

""

Does we have an option -lstd_v2 in gcc.
Where we need to include this option ie in compilation or linking.

In advance i wish u Very Happy New Year

Regards,
Gopi

[Dennis Handly]

>I found a statement which states as follows ... running the program will result in UnsatisfiedLinkErrors.

This should be for aC++ only, not C.

>Do we have an option -lstd_v2 in gcc?
>Where we need to include this option ie in compilation or linking.

This is a link option but I can't see how it would make it work, since you don't have any unsats.
What are the names of your native methods and are they in your shlib?
nm -px libIntroscopeHPUXItanium64Stats.so | grep " [TBD] "

[nallamolu]

Hi Dennis,

> nm -px libIntroscopeHPUXItanium64Stats.so | grep " [TBD] "

$ nm -px libIntroscopeHPUXItanium64Stats.so | grep " [TBD] "
0x4000000000001ca0 T JNU_ThrowByName
0x4000000000003000 T Java_com_hpux_HPUXPlatformStatisticsBackEnd_getAggregateCPUUsage
0x4000000000001ea0 T Java_com_hpux_HPUXPlatformStatisticsBackEnd_getCPUIndexMap
0x4000000000002ee0 T Java_com_hpux_HPUXPlatformStatisticsBackEnd_getParentProcessID
0x40000000000023a0 T Java_com_hpux_HPUXPlatformStatisticsBackEnd_getProcessCPUUsage
0x4000000000002dc0 T Java_com_hpux_HPUXPlatformStatisticsBackEnd_getProcessID
0x4000000000002d50 T Java_com_hpux_HPUXPlatformStatisticsBackEnd_getProtocolVersion
0x4000000000003be0 T Java_com_hpux_HPUXPlatformStatisticsBackEnd_getThreadCpuTime
0x40000000000025e0 T Java_com_hpux_HPUXPlatformStatisticsBackEnd_getTotalClockTicks
0x4000000000002d80 T Java_com_hpux_HPUXPlatformStatisticsBackEnd_init
0x4000000000003bb0 T Java_com_hpux_HPUXPlatformStatisticsBackEnd_isThreadCpuTimeEnabled
0x4000000000002da0 T Java_com_hpux_HPUXPlatformStatisticsBackEnd_term
0x40000000000002b0 D _DYNAMIC


1.) What are the compiling options for aCC(aC++) to compile in 64 bit mode ( HP-UX IA64 ).
Is it +DD64

> What are the names of your native methods and are they in your shlib?

The names of the native methods u can see above.

Does we nee to set shlib path. if yes to which location we need to set.

[Dennis Handly]

>1) What are the compiling options for aCC(aC++) to compile in 64 bit mode? Is it +DD64

Yes.

>The names of the native methods you can see above.

How are they declared in java?
Is this some class name? Java_com_hpux
What is JNU_ThrowByName for?

>Do we need to set SHLIB_PATH?

No, you aren't using any other shlibs.

I suppose you could use gdb to see what dl* functions are being called, dlopen, dlsym.