[vtkusers] bug fix to build on Linux/PowerPC

[Steven G. Johnson]

Hi, I am using Debian GNU/Linux on a PowerPC (Apple PowerBook G3), and I
ran into a small problem (easily fixed) in building VTK (using the nightly
VTK update as of Jul 21).  (A similar problem was present in version 3.2,
which was why I switched to the nightly update before attempting a fix.)

The problem is in common/vtkDynamicLoader.h, which has lines:

#elif defined(__powerpc)
  typedef ConnectionID vtkLibHandle;
#else

which, in the 3.2 sources, were used to support MacOS on PowerPCs.  
Obviously, this causes problems on Linux/PowerPC, for which __powerpc is
defined but MacOS types are not present.  Moreover, this code is not even
used any more; the corresponding routines in vtkDynamicLoader.cxx, which
is there in version 3.2, was deleted from the nightly version in favor of
new code for Darwin (& MacOS X).

So, the simplest fix seemed to be to delete it; here is the patch, after
which VTK builds successfully:

--- vtkDynamicLoader.h.orig	Sat Jul 21 13:41:36 2001
+++ vtkDynamicLoader.h	Sat Jul 21 13:41:04 2001
@@ -59,8 +59,6 @@
 #elif defined(_WIN32)
 # include "windows.h"
   typedef HMODULE vtkLibHandle;
-#elif defined(__powerpc)
-  typedef ConnectionID vtkLibHandle;
 #else
   typedef void* vtkLibHandle;
 #endif


(In the long run, it would really be better if you used autoconf to detect
this sort of thing, instead of relying upon compiler-specific ifdefs.)

I hope that this fix will make it into a future release; thanks!

Cordially,
Steven G. Johnson

PS. Sorry if this is not the right place for bug reports & patches; I
couldn't find any other contact addresses.