Benchmarks of code generated by different g++ versions

Question

I work on a runtime system for an application domain that is very performance sensitive. We go to a lot of effort to maintain backward compatibility with older compiler versions, including avoiding more recently-implemented language constructs, and synthesizing them for the older versions.

However, I'm concerned that this effort does a disservice to our users, by enabling them to continue to use compiler releases that are costing them huge amounts of performance. Unfortunately, I haven't been able to find any real comparison of execution performance across releases. If anyone has links to reports on this issue, please post them.

I'd really like to see benchmarks that cover a wide span of releases (if you can get back to 3.2, that's amazing) and applications/tests

Answer 1

A bit old, but still shows how much GCC have progressed: This benchmark shows that GCC 4.4 with it's new register allocator (IRA) and the focus on optimization made it become almost as powerful as ICC (Which is considered to be he most aggressive optimizer available).

I highly recommend using GCC 4.4[.1].

If you are on Windows, and using MinGW 3.4.x, you should upgrade NOW, since that specific port is rather buggy and generates horrible code.