The /usr/lib64/GNUstep/Makefiles/config.make file from the gnustep-make package contains:
#
# Whether the ObjC compiler supports native ObjC exceptions via
# @try/@catch/@finally/@throw.
#
USE_OBJC_EXCEPTIONS = no

The gnustep-base package reads this setting during build and builds itself without exception support.

This prevents proper using/building/packaging of programs that need both gnustep-base and exceptions (e.g. The Unarchiver, http://wakaba.c3.cx/s/apps/unarchiver.html).

Please consider adding "BuildRequires: gcc-objc" to gnustep-make.spec. It makes gnustep-make to detect exception support during the build and enable USE_OBJC_EXCEPTIONS. Rebuild of gnustep-base with enabled exceptions is then required.