Konstantin Kharlamov wrote:
I was told that e.g. "cold" attribute can sometimes produce
unbearably slow code
https://gcc.gnu.org/ml/gcc-help/2019-01/msg00035.html
Although cold functions can be slow, it appears that overall it's a
win for Emacs to mark _Noreturn error function declarations as cold:
on my platform, 'make compile-always' ran about 1.3% faster. So I
installed the attached patch into master. (Like Stefan, I'm wary of
marking functions 'hot' so I didn't do that.)
This patch also adds a convenience macro AVOID for the now-common
pattern '_Noreturn ATTRIBUTE_COLD void'.