On 7/3/20 11:47 AM, Mattias EngdegÄrd wrote: >> Having Emacs use --with-mfpmath=sse should improve performance a bit on x86. But >> more important, it should make floating point more reproducible. If I get the >> time I'll look into having 'configure' add it automatically. > Thank you, this would be a prerequisite for further improvements. Attached is a patch to do that. I looked at the GCC source code, and x86 is the only platform where this sort of thing should be necessary. I'll mention this patch on emacs-devel, to give people a heads-up before installing.