Hi,

Whilst working on the Reproducible Builds effort [0] we noticed that
ruby-regexp-parser could not be built reproducibly.

This is because it uses the ragel compiler that, by default, will add
line annotations that include the absolute build path:

  /usr/share/rubygems-integration/all/gems/regexp_parser-2.6.1/lib/regexp_parser/scanner.rb
  @@ -1,12 +1,12 @@
   # -*- warn-indent:false;  -*-

  -# line 1 "/build/1st/ruby-regexp-parser-2.6.1/tasks/../lib/regexp_parser/scanner/scanner.rl"
  +# line 1 "/build/2/ruby-regexp-parser-2.6.1/2nd/tasks/../lib/regexp_parser/scanner/scanner.rl"

(etc.)

A patch is attached that adjusts the call to ragel to include the -L
argument that suppresses these additions.

 [0] https://reproducible-builds.org/


Regards,