The sparc-rtems target currently uses init/fini for C++
constructors and without crti/n, they do not have the symbols.
OK, this is indeed done the same way (hijacking the Solaris files) for i386.
Longer term, both probably need to switch to how sparc-elf
does it but I was just trying to fix the breakage. And I didn't
build sparc64-rtems. This is how sparc-rtems has done it
for at least 10 years.
The patch is OK modulo the following couple of changes:
1) copy and adjust (x86 -> SPARC) the lines:
# This file was based on t-sol2 - x68 Solaris implementation. Actually,
# the source code to create crti.o anf crtn.o are exactly the same
# as the ones for Solaris. Later, we might want to have a RTEMS's
# version of these files.
from config/i386/t-rtems-i386 to the new config/sparc/t-rtems.
2) apply the config.gcc changes to both sparc-*-rtems* and sparc64-*-rtems*.