1085635 - Support building B2G with "ac_add_options --enable-warnings-as-errors", via .userconfig / "default-gecko-config" scripts

Status: RESOLVED DUPLICATE of bug 1073003

(Firefox OS Graveyard :: General, defect)

Description

[Daniel Holbert [:dholbert]]

Soon,[1] it should be conceivable for people to build B2G with --enable-warnings-as-errors (to enforce our existing FAIL_ON_WARNINGS annotations from moz.build files, in known-to-be-warning-free directories).

As far as I know, B2G's gecko is normally configured using a .userconfig file, which gets passed through  gonk-misc/default-gecko-config (I think?), which generates a mozconfig.  I don't think that process allows people to opt in to getting "ac_add_options --enable-warnings-as-errors". We should do whatever is required to make that possible. (maybe adding a new .userconfig variable which gets checked by default-gecko-config)

Moreover, we should make our TBPL builders opt into this, as we do for other platforms.  (but first things first, we need to make it available for people to use locally.)

[CC'ing a few folks who've touched gonk-misc/default-gecko-config in the past.]

[1] ("soon" because bug 915555 currently causes build warnings in pretty much every .cpp file everywhere, which means nothing is warning-free, which meant supposedly-warning-free-code would error-out. But once we start using a newer GCC version [bug 1077549], that should no longer be a problem.)

[2] https://github.com/mozilla-b2g/gonk-misc/blob/master/default-gecko-config

Comment 1

[Botond Ballo [:botond]]

Some relevant bugs I've filed recently:

  Bug 1073003 - Allow enabling warnings-as-errors from .userconfig 
  Bug 1073081 - Allow building with warnings-as-errors on B2G

Comment 2

[Daniel Holbert [:dholbert]]

Thanks! Yeah, I think this is a dupe of bug 1073003.