While GCC 7 is still under heavy development and the GCC 7.1 stable release will not come until a few months into 2017, here are some early benchmarks of GCC 7.0 compared to GCC 6.2 and GCC 5.4 on an Ubuntu Linux x86_64 system.
This weekend I ran some compiler comparison tests of freshly-built GCC 5.4.0, GCC 6.2.0, and GCC 7.0.0 20160904 compilers on a Xeon E5-2609 v4 system. During the automated open-source benchmarking process via the Phoronix Test Suite the CFLAGS/CXXFLAGS were set for "-O3 -march=native."
All the tests were done on the same Intel Xeon E5-2609 v4 Broadwell-EP system running Ubuntu 16.04 LTS with the Linux 4.8 x86_64 kernel. These tests are very straight-forward so let's get right to the interesting numbers.