Evil regex in pkgs/build-support/fetchurl/write-mirror-list.sh

[gitfoxi]

This line breaks my bootstrap on alpine linux:

grep '^[a-zA-Z]\+=.*://' > $out

This works. Tested on alpine and ubutnu:

egrep '^[a-zA-Z]+=.*://' > $out

[Profpatsch]

(triage) Needs severety:mass-rebuild.

Is it save to assume egrep?

[jpierre03]

(triage) @gitfoxi @Profpatsch @edolstra
cc @domenkozar @globin
Original file : https://github.com/NixOS/nixpkgs/blob/master/pkgs/build-support/fetchurl/write-mirror-list.sh
This file is unchanged since 2008.

PR #21861 created with @gitfoxi idea or maybe this issue can be closed ?

[vcunat]

Note: it doesn't rebuild anything, thanks to fetchurl producing fix-output derivations.

[jpierre03]

thanks