> On 2/12/20 8:53 PM, David Malcolm wrote: > The patch will need an update to the docs; search for > "Tools/packages necessary for building GCC" in > gcc/doc/install.texi, which currently has some paragraphs labelled: > @item ISO C++98 compiler > that will need changing.
Added this change in the attached patch. I looked through the rest of the docs folder for "C++98" mentions and found only those pertaining to using it in GCC rather than anything related to bootstrapping. Also did a grep for "C++98" in gcc as a whole and didn’t see any other places regarding bootstrapping. I modified how we check for C++11 to use "__cplusplus" since type_traits.h can be present even without full C++11 support. Testing on x86_64 on Ubuntu 18.04 with gcc 7.4.0 passes. Forcing bootstrap to use gcc 4.7 results in the following configure time error: **checking that the compiler supports c++11... configure: error: Building GCC requires a compiler that supports c++11, such as GCC 4.8.5 or newer** I believe RedHat has access to bootstrapping on a variety of platforms/native targets so if I can get someone to validate on those that would be great! That will also give a preview of what targets may have issues before this goes live. > From: gcc-ow...@gcc.gnu.org <gcc-ow...@gcc.gnu.org> On Behalf Of Mike > Stump > Sent: Friday, February 14, 2020 12:50 PM > I think we should pick not on the basis something unspecific, rather, I'd list > the 3 5 or 9 systems we check against, and then pick the minimum of them. > Above I picked 7.4 because it's on 18.04. I think this makes for a better > policy as it's predicable, stable, and in 100 years, I don't think I see the > need > to change the policy. I agree with Mike on having a policy in place to guide future efforts in this area. I'm not certain what type of upgrade cadence is needed (check versioning every major Release? Every 2? Note: this doesn't have to be part of the policy) but something consistent means (echoing Mike) there's a default mechanism and a "schedule" of when things are likely to come down the pipeline. Also Segher earlier in the thread linked to a great list compiled by Arnd Bergmann that shows Linux recommendations for GCC versioning which looks like a reasonable set of systems to check against. Here's the link again for ease of finding: https://lore.kernel.org/lkml/CAK8P3a3JfUjm88CLqkvAmCoEA1FsmQ33sfHGK4=y5iuhwxe...@mail.gmail.com/ Changelog entry for this patch: ChangeLog: 2020-02-25 Di Mo <mod...@microsoft.com> * configure.ac: Change bootstrap to test for and require C++11 support * configure: regenerate * gcc/doc/install.texi: Change bootstrapping requirement to C++11 Modi
c++11.patch
Description: c++11.patch
