A Look At The GCC 9 Performance On Intel Skylake Against GCC 8, LLVM Clang 7/8

With GCC 9 embarking upon its third stage of development where the focus ships to working on bug/regression fixes in preparation for releasing the GCC 9.1 stable compiler likely around the end of Q1'2019, here is a fresh look at the GCC 9 performance with its latest development code as of this week compared to GCC 8.2.0 stable while using an Intel Core i9 7980XE test system running Ubuntu Linux. For good measure are also fresh results from LLVM Clang 7.0 stable as well as LLVM Clang 8.0 SVN for the latest development state of that competing C/C++ open-source compiler.

As GCC 9 feature development is ending (aside from any new ports that may still be permitted during GCC Stage 3 development), it's a good time to check in on how this annual update to the GNU Compiler Collection is looking on the performance front. Both GCC 8.2 and GCC 9.0.0 20181112 were configured and built in the same manner from the Intel SKylake-X test system running Ubuntu 18.10 x86_64 with the Linux 4.18 kernel.

Clang 7.0 and Clang 8.0 SVN were also tested for reference on how that more liberally licensed compiler stack is performing. The CFLAGS/CXXFLAGS were set to "-O3 -march=native" and maintained the same flags throughout the building and benchmarking of all four compiler stacks.

These compiler benchmarks were carried out via the Phoronix Test Suite. As the GCC 9.1 stable release nears (along with Clang 8.0), there will be more compiler benchmarks on a diverse range of hardware for seeing how the performance pans out while this is just a preliminary look given the shift to the next stage of GCC development.