@Michael: does dropping support for 10.5 / 10.6 and opting into libc++ make sense? Shall I file a bug to track this?
Daniel On Wednesday, March 9, 2016 at 10:09:42 AM UTC-8, Nico Weber wrote: > > When building on OS X, you tell the compiler what the lowest OS X version > is that you want to support – this is the mac_deployment_target thing Jakob > mentioned. The SDK then makes certain functionality available only as weak > symbols (e.g. if you want to support running all the way back on 10.6, but > some function was introduced in 10.8, then that function is a weak symbol > and you have to make sure you check it to be non-NULL before you call it). > libc++ is the system library, so these weak symbol tricks don't work and > you need to explicitly tell the compiler which C++ standard library to use. > OS X started shipping a system libc++ in parallel to its very old libstdc++ > 4.2 in OS X 10.7. So if your deployment target is older than 10.7, you > cannot use the system libc++. If your deployment target is 10.9+ (I think), > then the compiler will use libc++ by default. If your deployment target is > 10.7 or 10.8 (iirc), you can opt in to libc++ but the default is still > libstdc++. > > All the C++11 stuff requires libc++, since Apple stopped updating their > libstdc++ long ago. > > For v8, the best recommendation is probably to drop support for 10.5 and > 10.6 (and maybe 10.7 and 10.8 too – Chromium is dropping support for > 10.6-10.8 in the next release), if you're able to do this. > > In Chromium, we jumped through some hoops to link against libc++ and still > target 10.6 for a few releases so we could use C++11 stuff earlier. > https://docs.google.com/document/d/1cFVCLYqpVV0pn2aX09SALcE3BN351sFN_rTcPcHRg3U/edit > > documents the approach, and Chromium's build files show how this was > implemented if you want to do that. But easiest is to just up your > deployment target to 10.7 and tell the compiler to use libc++. (To do this, > in gyp add 'CLANG_CXX_LIBRARY': 'libc++' to your xcode_settings block, and > in gn add "-stdlib=libc++" to your cflags_cc and ldflags.) > > On Wed, Mar 9, 2016 at 1:16 AM, Jakob Kummerow <jkum...@chromium.org > <javascript:>> wrote: > >> I think what Daniel was referring to is 'mac_deployment_target%': '10.5' >> in standalone.gypi, not the OS version that's actually installed on the >> bots. >> >> Maybe it's time to bump up the deployment target. Traditionally V8 has >> supported older OS versions than Chromium, but lacking tools like UMA it's >> really hard to estimate how important support for any given OS is in >> practice. >> >> >> On Wed, Mar 9, 2016 at 8:37 AM, Michael Achenbach <mache...@chromium.org >> <javascript:>> wrote: >> >>> The bots have all version 10.9.5. >>> >>> @Nico, what else would be required? Maybe there's something missing in >>> our standalone.gypi? >>> >>> On Mon, Mar 7, 2016 at 8:50 PM, Adam Klein <ad...@chromium.org >>> <javascript:>> wrote: >>> >>>> +machenbach, who maintains the bots. >>>> >>>> On Mon, Mar 7, 2016 at 11:18 AM, Daniel Cheng <dch...@chromium.org >>>> <javascript:>> wrote: >>>> >>>>> Who's responsible for maintaining these bots? It looks like v8_mac_rel >>>>> doesn't understand C++11 constructs still: >>>>> https://build.chromium.org/p/tryserver.v8/builders/v8_mac_rel/builds/16596 >>>>> >>>>> This seems to be related to -mmacosx-version-min=10.5: is there any >>>>> chance that we'll be dropping support for older OS X in V8 at some point? >>>>> >>>>> Daniel >>>>> >>>>> -- >>>>> -- >>>>> v8-dev mailing list >>>>> v8-...@googlegroups.com <javascript:> >>>>> http://groups.google.com/group/v8-dev >>>>> --- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "v8-dev" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>> an email to v8-dev+un...@googlegroups.com <javascript:>. >>>>> For more options, visit https://groups.google.com/d/optout. >>>>> >>>> >>>> -- >>>> -- >>>> v8-dev mailing list >>>> v8-...@googlegroups.com <javascript:> >>>> http://groups.google.com/group/v8-dev >>>> --- >>>> You received this message because you are subscribed to the Google >>>> Groups "v8-dev" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to v8-dev+un...@googlegroups.com <javascript:>. >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> >>> -- >>> -- >>> v8-dev mailing list >>> v8-...@googlegroups.com <javascript:> >>> http://groups.google.com/group/v8-dev >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "v8-dev" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to v8-dev+un...@googlegroups.com <javascript:>. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> > -- -- v8-dev mailing list v8-dev@googlegroups.com http://groups.google.com/group/v8-dev --- You received this message because you are subscribed to the Google Groups "v8-dev" group. 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