Debug build broken when using system spidermonkey

[Josh]

Since system provided SpiderMonkey (at least on Ubuntu) does not provide a debug build we should fail with a clear error message when trying to perform a debug build with --with-system-mozjs* if no debug library is present.

Possibly providing an option to create a debug build against SpiderMonkey release builds could be added, but as debug builds should provide as much information as possible this might not be useful.

[Josh]

Whoops! That patch only seems to fix the build, the linker still fails. The errors are here: ​http://pastebin.com/S7vs24NV.

[Yves]

Some additional information here (starting around 12:19): ​http://irclogs.wildfiregames.com/2014-05-14-QuakeNet-%230ad-dev.log

[historic_bruno]

Not really a release blocker, almost nobody uses debug builds... but thinking about it, this can't be much different than the past, Linux packagers don't typically provide debug builds do they?

[Josh]

It's not much different than it used to be, but the debug build no longer works with system spidermonkey libraries which is a regression.

[Yves]

We should probably link to the release binaries for debug builds. Having a system provided debug build does not make much sense because there are many different options that can be enabled for debugging different aspects of the Javascript engine or scripts. The only downside is that we have some useful debugging functionality enabled by default for custom debug builds and programmers could not be aware that they get better debugging functionality if they use the custom build instead of the system library.

[agentx]

probably relevant #2693

[historic_bruno]

This isn't really a release issue, since nobody releases debug builds, so I'm pushing to A18. We can take care of it then.

[Simon Georges]

Josh, is there a change on this issue with the recent update of Spider Monkey ?

[leper]

Rewrote the ticket since debug builds should use debug libraries and fail otherwise. Also moving to backlog.