Is there any built-in without a prototype?

On 5.28, prototype returns undef for at least the following (I may have missed a few, and I omitted most things that I think most people would classify as keywords and operators instead of functions, like use, goto, and -X):

chomp
chop
defined
delete
do
eval
exec
exists
grep
map
print
printf
require
return
say
select
sort
split
system
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Added minor clarifications.