Chris Bieneman
2014-Aug-22 16:42 UTC
[LLVMdev] [RFC] Raising LLVM minimum required MSVC version to 2013 for trunk
Starting a new thread to loop in cfe-dev and lldb-dev. For those not following along there has been a thread on llvm-dev about moving the minimum required Visual Studio version to 2013. The motivating reason is this will allow us to take advantage of a bunch of C++11 features that are not supported by MSVC 2012. According to MSDN (http://msdn.microsoft.com/en-us/library/hh567368.aspx) the list is: * Non-static data member initializers * Variadic templates * Initializer lists * Default template arguments for function templates * Expression SFINAE * Alias templates * Delegating constructors * Explicit conversion operators * Raw string literals * Defaulted and deleted functions From the discussion on LLVM-dev it is also believed that this may ease some development pain as people keep occasionally breaking LLVM trunk by using language features not available in MSVC. Original thread: http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075900.html <http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075900.html> Chandler’s proposal for moving forward is as follows: 1) Loop in cfe-dev and lldb-dev (Done!) 2) Wait until this email fully circulates in digests and LLVM Weekly so that everyone who has an objection can voice it 3) If there are no objections, Commit a change to the CMake build which errors on old MSVC versions 4) Revert and fix buildbots 5) Repeat 3 & 4 until no issues 6) Once the change is live for a week with no issues, update the documentation to reflect the minimum required MSVC version as 2013 (http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/076090.html <http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/076090.html>) Feedback is greatly appreciated. Thanks, -Chris -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20140822/4e5da269/attachment.html>
Daniel Dilts
2014-Aug-22 16:53 UTC
[LLVMdev] [RFC] Raising LLVM minimum required MSVC version to 2013 for trunk
On Fri, Aug 22, 2014 at 9:42 AM, Chris Bieneman <beanz at apple.com> wrote:> Starting a new thread to loop in cfe-dev and lldb-dev. For those not > following along there has been a thread on llvm-dev about moving the > minimum required Visual Studio version to 2013. The motivating reason is > this will allow us to take advantage of a bunch of C++11 features that are > not supported by MSVC 2012. >Is there an existing policy on how supported compiler versions are selected? -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20140822/b6a5e33f/attachment.html>
Chris Bieneman
2014-Aug-22 16:58 UTC
[LLVMdev] [RFC] Raising LLVM minimum required MSVC version to 2013 for trunk
> On Aug 22, 2014, at 9:53 AM, Daniel Dilts <diltsman at gmail.com> wrote: > > On Fri, Aug 22, 2014 at 9:42 AM, Chris Bieneman <beanz at apple.com <mailto:beanz at apple.com>> wrote: > Starting a new thread to loop in cfe-dev and lldb-dev. For those not following along there has been a thread on llvm-dev about moving the minimum required Visual Studio version to 2013. The motivating reason is this will allow us to take advantage of a bunch of C++11 features that are not supported by MSVC 2012. > > Is there an existing policy on how supported compiler versions are selected?There was a discussion last year (http://lists.cs.uiuc.edu/pipermail/llvmdev/2013-October/066847.html <http://lists.cs.uiuc.edu/pipermail/llvmdev/2013-October/066847.html>) WRT allowing LLVM to use C++11 features which established a precedent of supporting compilers released back for two years, with a special caveat for Windows. -Chris -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20140822/6259bcbf/attachment.html>
Aaron Ballman
2014-Sep-29 23:45 UTC
[LLVMdev] [RFC] Raising LLVM minimum required MSVC version to 2013 for trunk
On Fri, Aug 22, 2014 at 12:42 PM, Chris Bieneman <beanz at apple.com> wrote:> Starting a new thread to loop in cfe-dev and lldb-dev. For those not > following along there has been a thread on llvm-dev about moving the minimum > required Visual Studio version to 2013. The motivating reason is this will > allow us to take advantage of a bunch of C++11 features that are not > supported by MSVC 2012. According to MSDN > (http://msdn.microsoft.com/en-us/library/hh567368.aspx) the list is: > > * Non-static data member initializers > * Variadic templates > * Initializer lists > * Default template arguments for function templates > * Expression SFINAE > * Alias templates > * Delegating constructors > * Explicit conversion operators > * Raw string literals > * Defaulted and deleted functions > > From the discussion on LLVM-dev it is also believed that this may ease some > development pain as people keep occasionally breaking LLVM trunk by using > language features not available in MSVC. > > Original thread: > http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075900.html > > Chandler’s proposal for moving forward is as follows: > 1) Loop in cfe-dev and lldb-dev (Done!) > 2) Wait until this email fully circulates in digests and LLVM Weekly so that > everyone who has an objection can voice it > 3) If there are no objections, Commit a change to the CMake build which > errors on old MSVC versions > 4) Revert and fix buildbots > 5) Repeat 3 & 4 until no issues > 6) Once the change is live for a week with no issues, update the > documentation to reflect the minimum required MSVC version as 2013 > > (http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/076090.html) > > Feedback is greatly appreciated.This thread has sort of stalled without a resolution. Alex, has your team had the opportunity to weigh in on the subject yet? We have run into a hard situation where MSVC 2012 is missing a feature that we are currently relying on. We made some changes to ASTMatchers to reduce the number of symbols generated in order to not require /bigobj support (see http://reviews.llvm.org/D5485). This change relies on function templates with default arguments, which MSVC does not support (it generates a C4519 error in MSVC 2012), resulting in red bots (http://bb.pgr.jp/builders/ninja-clang-i686-msc17-R/builds/10721). This is a considerably more interesting case (at least to me) than hypothetical benefits -- if we retain MSVC 2012 support, we will also require /bigobj support, have slower compile times for ASTMatcher projects, and slower benchmarks for clang-tidy. This points to concrete benefits to expediting switching away from MSVC 2012, which is why I am pinging this thread again. Thanks! ~Aaron
Robinson, Paul
2014-Sep-30 04:14 UTC
[LLVMdev] [cfe-dev] [RFC] Raising LLVM minimum required MSVC version to 2013 for trunk
> -----Original Message----- > From: cfe-dev-bounces at cs.uiuc.edu [mailto:cfe-dev-bounces at cs.uiuc.edu] On > Behalf Of Aaron Ballman > Sent: Monday, September 29, 2014 4:45 PM > To: Chris Bieneman > Cc: lldb-dev at cs.uiuc.edu; cfe-dev Developers; LLVM Developers Mailing List > Subject: Re: [cfe-dev] [LLVMdev] [RFC] Raising LLVM minimum required MSVC > version to 2013 for trunk > > On Fri, Aug 22, 2014 at 12:42 PM, Chris Bieneman <beanz at apple.com> wrote: > > Starting a new thread to loop in cfe-dev and lldb-dev. For those not > > following along there has been a thread on llvm-dev about moving the > minimum > > required Visual Studio version to 2013. The motivating reason is this > will > > allow us to take advantage of a bunch of C++11 features that are not > > supported by MSVC 2012. According to MSDN > > (http://msdn.microsoft.com/en-us/library/hh567368.aspx) the list is: > > > > * Non-static data member initializers > > * Variadic templates > > * Initializer lists > > * Default template arguments for function templates > > * Expression SFINAE > > * Alias templates > > * Delegating constructors > > * Explicit conversion operators > > * Raw string literals > > * Defaulted and deleted functions > > > > From the discussion on LLVM-dev it is also believed that this may ease > some > > development pain as people keep occasionally breaking LLVM trunk by > using > > language features not available in MSVC. > > > > Original thread: > > http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075900.html > > > > Chandler’s proposal for moving forward is as follows: > > 1) Loop in cfe-dev and lldb-dev (Done!) > > 2) Wait until this email fully circulates in digests and LLVM Weekly so > that > > everyone who has an objection can voice it > > 3) If there are no objections, Commit a change to the CMake build which > > errors on old MSVC versions > > 4) Revert and fix buildbots > > 5) Repeat 3 & 4 until no issues > > 6) Once the change is live for a week with no issues, update the > > documentation to reflect the minimum required MSVC version as 2013 > > > > (http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/076090.html) > > > > Feedback is greatly appreciated. > > This thread has sort of stalled without a resolution. Alex, has your > team had the opportunity to weigh in on the subject yet?I'm expecting to have our internal builds switched over later this week. Our investigations have shown no problems.> > We have run into a hard situation where MSVC 2012 is missing a feature > that we are currently relying on. We made some changes to ASTMatchers > to reduce the number of symbols generated in order to not require > /bigobj support (see http://reviews.llvm.org/D5485). This change > relies on function templates with default arguments, which MSVC does > not support (it generates a C4519 error in MSVC 2012), resulting in > red bots (http://bb.pgr.jp/builders/ninja-clang-i686-msc17- > R/builds/10721).I have a sad bot failing to build in Debug mode, glad to know there's a fix in the works.> > This is a considerably more interesting case (at least to me) than > hypothetical benefits -- if we retain MSVC 2012 support, we will also > require /bigobj support, have slower compile times for ASTMatcher > projects, and slower benchmarks for clang-tidy. This points to > concrete benefits to expediting switching away from MSVC 2012, which > is why I am pinging this thread again.I guess I'm a little surprised that /bigobj is such a compile-time hit, but haven't tried any benchmarking. Anyway, whatever works best for you. --paulr> > Thanks! > > ~Aaron > > _______________________________________________ > cfe-dev mailing list > cfe-dev at cs.uiuc.edu > http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev
Alexander Kornienko
2014-Sep-30 09:05 UTC
[LLVMdev] [cfe-dev] [RFC] Raising LLVM minimum required MSVC version to 2013 for trunk
On Tue, Sep 30, 2014 at 3:45 AM, Aaron Ballman <aaron at aaronballman.com> wrote:> On Fri, Aug 22, 2014 at 12:42 PM, Chris Bieneman <beanz at apple.com> wrote: > > Starting a new thread to loop in cfe-dev and lldb-dev. For those not > > following along there has been a thread on llvm-dev about moving the > minimum > > required Visual Studio version to 2013. The motivating reason is this > will > > allow us to take advantage of a bunch of C++11 features that are not > > supported by MSVC 2012. According to MSDN > > (http://msdn.microsoft.com/en-us/library/hh567368.aspx) the list is: > > > > * Non-static data member initializers > > * Variadic templates > > * Initializer lists > > * Default template arguments for function templates > > * Expression SFINAE > > * Alias templates > > * Delegating constructors > > * Explicit conversion operators > > * Raw string literals > > * Defaulted and deleted functions > > > > From the discussion on LLVM-dev it is also believed that this may ease > some > > development pain as people keep occasionally breaking LLVM trunk by using > > language features not available in MSVC. > > > > Original thread: > > http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075900.html > > > > Chandler’s proposal for moving forward is as follows: > > 1) Loop in cfe-dev and lldb-dev (Done!) > > 2) Wait until this email fully circulates in digests and LLVM Weekly so > that > > everyone who has an objection can voice it > > 3) If there are no objections, Commit a change to the CMake build which > > errors on old MSVC versions > > 4) Revert and fix buildbots > > 5) Repeat 3 & 4 until no issues > > 6) Once the change is live for a week with no issues, update the > > documentation to reflect the minimum required MSVC version as 2013 > > > > (http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/076090.html) > > > > Feedback is greatly appreciated. > > This thread has sort of stalled without a resolution. Alex, has your > team had the opportunity to weigh in on the subject yet? > > We have run into a hard situation where MSVC 2012 is missing a feature > that we are currently relying on. We made some changes to ASTMatchers > to reduce the number of symbols generated in order to not require > /bigobj support (see http://reviews.llvm.org/D5485). This change > relies on function templates with default arguments, which MSVC does > not support (it generates a C4519 error in MSVC 2012), resulting in > red bots (http://bb.pgr.jp/builders/ninja-clang-i686-msc17-R/builds/10721 > ). > > This is a considerably more interesting case (at least to me) than > hypothetical benefits -- if we retain MSVC 2012 support, we will also > require /bigobj support, have slower compile times for ASTMatcher > projects, and slower benchmarks for clang-tidy. This points to > concrete benefits to expediting switching away from MSVC 2012, which > is why I am pinging this thread again. >We regularly stumble upon C++11 features not supported by MSVC 2012 and have to rollback patches after some buildbot breaks. Usually, it's easy to work around, not sure about this case. It's probably better to ask the author of http://reviews.llvm.org/rL218616. So I'm personally both hands for switching the minimal supported MSVC version to 2013. I understand though, that by requiring MSVC 2013, instead of missing support of some language features we could get incomplete and buggy support. But still looks like a better alternative to me. -- Alex> Thanks! > > ~Aaron > >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20140930/e31f9a2e/attachment.html>
Apparently Analagous Threads
- [LLVMdev] [cfe-dev] [RFC] Raising LLVM minimum required MSVC version to 2013 for trunk
- [LLVMdev] [RFC] Raising minimum required Visual Studio version to 2013 for trunk
- [LLVMdev] [RFC] Raising minimum required Visual Studio version to 2013 for trunk
- [LLVMdev] [RFC] Raising minimum required Visual Studio version to 2013 for trunk
- [LLVMdev] [RFC] Raising minimum required Visual Studio version to 2013 for trunk