title: PostgreSQL installing from source - conflicting types for 'copy_file_range' error
body: <p>I'm currently trying to install a previous version of Postgresql from the source code, however after unzipping the tarball and running the "make" command to create the binaries I run into this error:</p>
  
  <p><code>copy_fetch.c:161:1: error: conflicting types for ‘copy_file_range’
   copy_file_range(const char *path, off_t begin, off_t end, bool trunc)
   ^~~~~~~~~~~~~~~
  In file included from copy_fetch.c:16:0:
  /usr/include/unistd.h:1110:9: note: previous declaration of ‘copy_file_range’ was here</code></p>
  
  <p>I can see on the Postgres message boards there has been talk about renaming copy_file_range(): <a href="https://www.postgresql.org/message-id/E1eWpqd-00067Q-2b%40gemulon.postgresql.org" rel="nofollow noreferrer">https://www.postgresql.org/message-id/E1eWpqd-00067Q-2b%40gemulon.postgresql.org</a></p>
  
  <p>Does anyone know what steps are needed to resolve this issue? The version of Postgres I am trying to install is 9.5.</p>