GCC 8/9 vs. LLVM Clang 7/8 Compiler Performance On AArch64

In other common real-world tests, GCC tended to deliver slightly faster performance than Clang on this 64-bit 32-core ARM server.

If wanting to look at even more raw performance data from this GCC vs. Clang compiler benchmark comparison, the dozens of results can be viewed in full via this OpenBenchmarking.org result file.

If looking at the geometric mean for all of the test runs that successfully ran across all four compilers, GCC comes out ahead but with little difference between last year's GCC8 code-base and the upcoming GCC9. Likewise, between Clang 7.0 and 8.0 wasn't any real difference on the macro level for performance. On this powerful Ampere eMAG server, using GCC yielded 23% better performance than the Clang-built binaries. With the recent x86_64 compiler benchmarks the performance was a toss-up between GCC and Clang while on the POWER9 Talos II the GNU Compiler Collection had around a 10% performance advantage for the geometric mean.

Look for Clang 8.0 to be shipping around the end of February while GCC 9.1 is due for release around April.