/usr/lib64/libgeos-3.6.1.so and /usr/lib64/libgeos_c.so.1.10.1 in geos-3.6.1-7.fc28.x86_64 have not been linked with the standard Fedora linker flags (LDFLAGS) from redhat-rpm-config. It looks like -specs=/usr/lib/rpm/redhat/redhat-hardened-ld was dropped from LDFLAGS: libtool: link: g++ -fPIC -DPIC -shared -nostdlib /usr/lib/gcc/x86_64-redhat-linux/8/../../../../lib64/crti.o /usr/lib/gcc/x86_64-redhat-linux/8/crtbeginS.o .libs/inlines.o -Wl,--whole-archive algorithm/.libs/libalgorithm.a geom/.libs/libgeom.a geomgraph/.libs/libgeomgraph.a index/.libs/libindex.a io/.libs/libio.a linearref/.libs/liblinearref.a noding/.libs/libnoding.a operation/.libs/liboperation.a planargraph/.libs/libplanargraph.a precision/.libs/libprecision.a simplify/.libs/libsimplify.a triangulate/.libs/libtriangulate.a util/.libs/libutil.a -Wl,--no-whole-archive -L/usr/lib/gcc/x86_64-redhat-linux/8 -L/usr/lib/gcc/x86_64-redhat-linux/8/../../../../lib64 -L/lib/../lib64 -L/usr/lib/../lib64 -L/usr/lib/gcc/x86_64-redhat-linux/8/../../.. -lstdc++ -lm -lc -lgcc_s /usr/lib/gcc/x86_64-redhat-linux/8/crtendS.o /usr/lib/gcc/x86_64-redhat-linux/8/../../../../lib64/crtn.o -O2 -g -fstack-protector-strong -grecord-gcc-switches -m64 -mtune=generic -mcet -Wl,-z -Wl,relro -Wl,-soname -Wl,libgeos-3.6.1.so -o .libs/libgeos-3.6.1.so /usr/lib64/python2.7/site-packages/geos/_geos.so in python2-geos-3.6.1-7.fc28.x86_64 also needs fixing, but that will likely arrive through a fix in distutils. See https://src.fedoraproject.org/rpms/redhat-rpm-config/blob/master/f/buildflags.md for information on RPM macros and environment variables provided by the build environment.
I've talked with Florian, a simple rebuild adds the required -Wl,now to the linker command. -specs isn't required atm.
geos-3.6.1-8.fc28 has been submitted as an update to Fedora 28. https://bodhi.fedoraproject.org/updates/FEDORA-2018-7d25f86e9a
geos-3.6.1-8.fc28 has been pushed to the Fedora 28 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2018-7d25f86e9a
geos-3.6.1-8.fc28 has been pushed to the Fedora 28 stable repository. If problems still persist, please make note of it in this bug report.