1378592 - Remove MOZ_REPLACE_MALLOC_LINKAGE

Status: RESOLVED FIXED

(Firefox Build System :: General, enhancement)

Comment 1

[Mike Hommey [:glandium]]

Attachment: Bug 1378592 - Remove MOZ_REPLACE_MALLOC_LINKAGE.

MOZ_REPLACE_MALLOC_LINKAGE was added back when there were problems with
getting weak references working properly for replace-malloc.

Versions of OSX < 10.6 needed flat namespace, but aren't supported
anymore.

Versions of Xcode < 4.5 required flat namespace + a dummy library in
order to produce proper weak references. There is virtually nobody still
building with such an ancient toolchain.

Keeping those around doesn't /really/ hurt, except recent versions of
Xcode don't expose dyldinfo in /usr/bin, used for the configure test.
Consequently, MOZ_REPLACE_MALLOC_LINKAGE ended up being set to use the
dummy library setup, which, by using flat namespace, now causes harm in
bug 1356701, causing bug 1378332.

Review commit: https://reviewboard.mozilla.org/r/154740/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/154740/

Comment 2

[Nathan Froyd [:froydnj]]

Comment on attachment 8883787 [details]
Bug 1378592 - Remove MOZ_REPLACE_MALLOC_LINKAGE.

https://reviewboard.mozilla.org/r/154740/#review159980

I would love to have my confusion below cleared up somehow.

::: commit-message-508a3:13
(Diff revision 1)
> +Keeping those around doesn't /really/ hurt, except recent versions of
> +Xcode don't expose dyldinfo in /usr/bin, used for the configure test.

I don't fully grok this claim.  If all that matters is the configure test, we (seemingly) have all the info we need for this in the cross-compilation setup, right?  So it doesn't really explain why nightlies were busted--though it's possible I'm missing something.  Or were we getting the wrong answer because cross-compiles were returning the wrong thing?

It would definitely affect people building locally, I guess, so it's good to get it fixed up one way or another.

::: old-configure.in
(Diff revision 1)
> -if test -n "$MOZ_REPLACE_MALLOC"; then
> -    dnl Replace-malloc Mac linkage quirks

Getting rid of this much of old-configure.in in one shot is great.

Comment 3

[Mike Hommey [:glandium]]

Automation builds weren't actually affected. They were using "compiler support" already:

[task 2017-07-06T15:56:00.452885Z] 15:56:00     INFO -  checking how to do weak dynamic linking... compiler support

Note *this bug* does not address what busted nightlies, but bug 1378332, as mentioned in the commit message. What busted the nightlies is addressed in bug 1356701 itself.

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/67324ef6c302
Remove MOZ_REPLACE_MALLOC_LINKAGE. r=froydnj

Comment 5

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/67324ef6c302