[gmx-developers] Re: help needed: static builds with cmake

[Justin A. Lemkul]

Roland Schulz wrote:
> 
> 
> On Thu, Oct 28, 2010 at 3:47 PM, Szilárd Páll <szilard.pall at cbr.su.se 
> <mailto:szilard.pall at cbr.su.se>> wrote:
> 
>      >> 1) works fine, but referring to file extensions/endings might not be
>      >> general enough. Making it more general/robust would require
>     rewriting
>      >> the way external libraries are treated: instead of adding them with
>      >> full path we'd need to add -Lpath -llibname separately. However,
>     this
>      >> needs quite a bit more time than I have now...
>      >
>      > I'm confused, is the later part ( -Lpath -llibname separately)
>     part of the
>      > 2nd step below. Or not? Why does it take a lot of time?
> 
>     Probably not a lot, but it smells like it's is/might turn out to be
>     more then I have ATM :)
>     The cmake find scripts (maybe not all, but most) do not return a
>     separate library name and library path.
> 
> 
> Now I understand. BTW: their is a CMAKE_STATIC_LIBRARY_SUFFIX. You can 
> use that instead of specifying ".a" directly.
> 
> 
>      >>
>      >> 2) Should work with the target property LINK_SEARCH_END_STATIC which
>      >> essentially puts a -Wl,-Bstatic (for gcc on Linux, but it's supposed
>      >> to work on many platforms) at the end of the final link call
>     argument
>      >> list.
>      >
>      > If the later part of step 1 above has not been done, than how
>     does it help
>      > to set "-Wl,-Bstatic"? Does it use the static version even when
>     you specify
>      > the library file with the full path?
> 
>      From the Cmake docs:
>     "LINK_SEARCH_END_STATIC: End a link line such that static system
>     libraries are used."
> 
>     If I understand correctly, when "-Wl,-Bstatic" is placed at the end of
>     the link argument list  it does not affect the arguments that precede
>     it and therefor 1) and 2) could work together, just that if e.g. fftw
>     is only available as shared library, this would be linked in
>     dynamically.
> 
> 
>  Too me this looks like a bug in cmake. It has 
> (in Modules/Platform/Linux.cmake) LINK_STATIC_C_FLAGS "-Wl,-Bstatic". 
> But I think it should include the -static for gcc. It might have been 
> sufficient to have the Wl,-Bstatic but at least now gcc requires also 
> the static option. If you agree we should file a cmake bug report.
> 

I don't know a whole lot about the ins and outs of compiler options, but I do 
know that on Mac OSX systems, gcc -static can frequently cause problems, i.e.:

http://stackoverflow.com/questions/844819/how-to-static-link-on-os-x

-Justin

> Does step 1 apply to the gromacs internal libraries (libmd, libgmx, ..)? 
> If so, I think step 1 by itself is good enough. 
> 
> Roland
> 
> -- 
> ORNL/UT Center for Molecular Biophysics cmb.ornl.gov <http://cmb.ornl.gov>
> 865-241-1537, ORNL PO BOX 2008 MS6309
> 

-- 
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Justin A. Lemkul
Ph.D. Candidate
ICTAS Doctoral Scholar
MILES-IGERT Trainee
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin

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