gcc5 from Virtualization:containers:ppc64le_with_gc_go project
Select Your Operating System
Add repository and install manually
For SLE 12 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/Virtualization:containers:ppc64le_with_gc_go/SLE_12/Virtualization:containers:ppc64le_with_gc_go.repo zypper refresh zypper install gcc5