topic Re: Wondering how to create linker map? in Operating System - Linux

Wondering how to create linker map ?

kraft — Mon, 22 Jan 2007 10:13:31 GMT

I am on hp-ux itanium the compiler and linker I am using is aCC, tried -m option, but still can get it work. Anything I am overlooked? Thanks!

Re: Wondering how to create linker map ?

A. Clay Stephenson — Mon, 22 Jan 2007 11:09:58 GMT

You have to tell the compiler to send the -m option to the linker phase of the operation. Something like this:

aCC -Wl,-m myfile.c

This will output a map on stdout.

Re: Wondering how to create linker map ?

kraft — Mon, 22 Jan 2007 13:22:38 GMT

Thanks! This works. One more question, how to display the library ( eg .o, .so) that my program linked with ?

Re: Wondering how to create linker map ?

A. Clay Stephenson — Mon, 22 Jan 2007 13:28:20 GMT

ldd myprogram. ldd -> list dynamic dependencies. Man ldd for details.

Re: Wondering how to create linker map ?

Peter Nikitka — Mon, 22 Jan 2007 13:28:55 GMT

Hi,

call
chatr yourlinkedobject

that will tell used runtime libraries (and more).

mfG Peter

Re: Wondering how to create linker map ?

kraft — Mon, 22 Jan 2007 14:23:41 GMT

Thank you every one. Bear with me I am quite new in hp-ux. One more question what's the different between .o and .so. Is .so like dll on windows?

Re: Wondering how to create linker map ?

A. Clay Stephenson — Mon, 22 Jan 2007 14:51:18 GMT

Well, it would be more accurate to say that .DLL's are like .so's since UNIX had them before there was even a Windows but .so are shared objects. Essentially that means that you have to turn on some compiler options to make the code relocatable. In HP-UX, .so's are more often .sl's but it's the same thing. You need to become familiar with two commands: nm and file. For example, file myfile.so will tell you what kind of file myfile.so is. nm will dump the symbol table of an object file, library, or executable. Man file and nm for details.

Re: Wondering how to create linker map ?

kraft — Mon, 22 Jan 2007 16:03:54 GMT

Again, Thank you for your help

Re: Wondering how to create linker map?

Dennis Handly — Sat, 22 Oct 2011 00:32:01 GMT

Why would you want to use -m?

You can get this info from elfdump(1):
$ elfdump -S -h a.out

You can use aCC +help or the following for aC++ help:
http://docs.hp.com/en/8759/index.htm

If you want to display the objects/libs you are linked with: -Wl,-t

>Clay: Essentially that means that you have to turn on some compiler options to make the code relocatable. In HP-UX, .so's are more often .sl's

The default on IPF is PIC, so no options are needed. Also on IPF, you should name your shlibs as .so, not the the PA convention of .sl.

>nm will dump the symbol table of an object file, library, or executable.

elfdump -t is the correct tool to work on shlibs and executables, if you are using tricky linker options:
$ elfdump -s -n .dynsym a.out

Re: Wondering how to create linker map ?

kraft — Tue, 23 Jan 2007 10:11:17 GMT

Dennis, these works as well. Thanks!

Rather starting a new thread, I would like ask here, this is regarding stack trace. I know there are a macro we can use U_STACK_TRACE, just wondering if there are any other ways ? I have a program which crashed very strangely. I don't know the signal would be when it crashes. I tried SIGQUIT, but it wasn't. What I would like to do is whenever it crashes, it creates a stack trace. Any suggestions ?

Re: Wondering how to create linker map?

Dennis Handly — Sat, 22 Oct 2011 00:32:28 GMT

>I don't know the signal would be when it crashes. I tried SIGQUIT, but it wasn't. What I would like to do is whenever it crashes, it creates a stack trace.

You can use a debugger to figure out the signal. Also "file core" should tell you the signal.

You could call U_STACK_TRACE() from your signal handler. You must arm your handler for the signals you expect to catch. The latest version of libunwind will print the signal #.