"make check" times

[Paul Eggert]

On 10/5/20 2:51 PM, DJ Delorie via Libc-alpha wrote:
> Is printf a guaranteed builtin in posix shells?

It's not a "Special Built-In Utility" in the POSIX sense, but neither are 'echo' 
or 'read'.

To answer what I think is your real question, these days I believe that "printf 
'%s\n' 'FOO'" is typically nearly as fast as "echo 'FOO'" on the shells that 
glibc developers use. I just tried a simple benchmark with bash and dash on 
Ubuntu 20.04 x86-64 with a loop that just output 'x' on a line, and the echo 
version was about 20% faster with dash and about 15% faster with Bash.