Re: [micro-manager-general] please add missing .la files to FreeImage and FreeImagePlus build

[Nico S. <ni...@cm...>]

On Nov 15, 2011, at 2:21 PM, Stefan Schoenleitner wrote:

> when working with SimpleCam/gphoto, I discovered that in
> 3rdpartypublic/FreeImage there are no libfreeimage.la and
> libfreeimageplus.la files when the FreeImage build completes.

Correct me if I am wrong, but those libtool files are platform dependent and you will need to generate these yourself if you need them.

> Since the micro-manager building code heavily relies on libtool, some
> linking issues arise if these files are missing.
> For instance, in DeviceAdapters/SimpleCam/Makefile.am, the FreeImage
> libraries are correctly added to the build process with:
> 
> ------------------------------------------------
> libmmgr_dal_GPhoto_la_LIBADD += $(LIBFREEIMAGE)
> ------------------------------------------------
> 
> However, since there are no .la files, $(LIBFREEIMAGE) is empty and the
> resulting .so file misses the dependencies to the FreeImage libraries.
> Thus, even through the .so file builds just fine, loading the file will
> ultimately fail with unresolved symbols.
> 
> The solution is to either add .la file generation so freeImage, or
> link code like SimpleCam statically with:
> 
> ------------------------------------------------
> libmmgr_dal_GPhoto_la_LIBADD += /usr/local/lib/libfreeimage.a
> libmmgr_dal_GPhoto_la_LIBADD += /usr/local/lib/libfreeimageplus.a
> ------------------------------------------------
> 
> Obviously, the latter option is not a good choice since, apart from the
> static linking, it relies on fixed file locations.

DeviceAdapter2/configure.in contains the following:

   AC_FIND_FILE([libfreeimage.a], [/usr/lib /usr/lib64 /usr/local/$ARCH/lib], FREEIMAGELIBDIR)
   if test x$FREEIMAGELIBDIR = xNO; then
      buildsc=false
      AC_MSG_RESULT(["libfreeimage.a" not found...])
   else
      AC_MSG_RESULT(["libfreeimage.a" found])
      AC_SUBST(LIBFREEIMAGE, "$FREEIMAGELIBDIR/libfreeimage.a")
      AC_SUBST(LIBFREEIMAGE_CXXFLAGS, "-I../../../3rdpartypublic/FreeImage/Dist -I../../../3rdpartypublic/FreeImage/Wrapper/FreeImagePlus ")  
   fi  


So, as long as you have a libfreeimage.a in /usr/lib,  /usr/lib64, or /usr/local/$ARCH/lib, then the variable LIBFREEIMAGE should be set up correctly for static linking.

I really prefer static linking on the Mac, since this ensures that everything is where it should be.  If you want things differently on Linux, send me a patch (that should not break things on the Mac).

Best,

Nico