I just noticed that http://perldoc.perl.org/index-functions-by-cat.html#Keywords-related-to-control-flow-of-your-perl-program doesn't list while and until but goto and that the latter is linkable: goto

Looks like the root cause

update

The former html page seems to be an excerpt from perlfunc#Perl-Functions-by-Category , which also lists

• Non-function keywords

and , AUTOLOAD , BEGIN , CHECK , cmp , CORE ,__DATA__ , default 
, DESTROY , else , elseif, elsif , END ,__END__ , eq , for , foreach 
, ge , given , gt , if , INIT , le , lt , ne , not , or , UNITCHECK 
, unless ,until , when , while , x , xor
[download]

This is unfortunate ...

update

This seems to be the source of cross references used to resolve while

perlfunc#Non-function-Keywords-by-Cross-reference