The default NetBSD/sparc /usr/lib/c++rt0.o is compiled -fpic. This means
it can only handle offsets up to a certain size, and can fail to work in
large programs. Compiling -fPIC allows larger offsets and should permit
large programs to function. As mixing object files compiled with -fpic
and -fPIC isn't allowed, the system c++rt0.o must be exchanged so that
-fPIC can be used everywhere. 

This package allows most of pkgsrc to compile on NetBSD/sparc systems
which run an OS version prior to 1.4.3 (which already contains this fix).