Re: Setting option flags for building system libraries

[Andrew Johnson <anj@aps.anl.gov>]

Hi David,

David Dudley wrote:
> 1. To build a relocatable library for libCom, I have to pass options
> "-shared -fPIC" through to g++ when I'm creating the relocatable
> library.  This works fine, and I can create and use the library sort
> of successfully.  I'm still looking for the exact variable to set to
> pass these values.  have tried setting about every variable in my new
> "CONFIG.Common.netbsd-x86" file, and currently have it set in
> COMPILER_LDFLAGS.  However, when I run gmake with these options
> selected in  COMPILER_LDFLAGS, it will create a properly library, but
> fails to create a proper executable.
>
> 2. To build an executable, I have to be sure NOT to pass the 
> "-shared" option through to g++.  I demonstrated that this works by 
> deleting the incorrectly build 'antelope' program that is linked 
> after the library is built, delete the "-shared" flag from my new 
> "CONFIG.Common.netbsd-x86" file and rerun gmake.  This will recreate 
> the antelope program, which appears to be functional.

Hmm, I think there may be a problem here which means you might not be 
able to create shared libraries for NetBSD.  Can I make sure I'm 
understanding your point first though:

1. To compile code for a .so, you *must* pass '-shared' to the gcc or 
g++ command line when you compile the .c/.cc/.cxx file.
2. To compile code for an executable (and presumably for a lib.a file), 
you *must* *not* pass '-shared' to the gcc/g++ command line.

If those statements are both correct, I think you're going to have to 
disable the building of shared libraries since I believe we have no way 
to recompile a source file with different options to generate two 
different .o files from the same source.

You can disable building shared libraries by setting SHARED_LIBRARIES=NO 
in your CONFIG.Common.netbsd-x86 file.  I would recommend that you do 
that anyway for now and come back to the .so problem later.

> Looks like most of the Make files were done by jba (I'm taking that 
> to be Janet Anderson, I hope... She still doing work on this, or 
> anyone have a suggestion?

Yes, JBA is Janet Anderson <jba@aps.anl.gov> who is responsible for the 
build system.

David Dudley wrote:
> Well, I'm sure it won't run correctly, but    ***IT COMPILES WITHOUT ERRORS***!

Congratulations!  I assume you ignored or disabled the .so builds to get 
to this point.

- Andrew
--
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of the smartest bears and the dumbest tourists.
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