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    <p>Thanks for the responses, it looks like making VS2019 the minimum
      supported version sooner rather than later will help a number of
      cases.</p>
    <p>I'll create a patch this weekend, for review next week when more
      people are back after the USA holiday.</p>
    <p>Simon.<br>
    </p>
    <div class="moz-cite-prefix">On 25/11/2021 12:57, James Henderson
      via llvm-dev wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:CABqSp3m=fhprJMUtaoWR-PgzpViGX_u0wczyj8n3NyZpxUeXoA@mail.gmail.com">
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        <div>I'm also personally in favour of this - a couple of months
          ago I ran into a bug with the VS2017 compiler that isn't
          present in the VS2019 one, that was preventing me using
          std::enable_if in a way I'd have liked to. Being able to
          retire VS2017 support would simplify a few things for me.</div>
        <div><br>
        </div>
        <div>James<br>
        </div>
      </div>
      <br>
      <div class="gmail_quote">
        <div dir="ltr" class="gmail_attr">On Thu, 25 Nov 2021 at 12:30,
          Jan Svoboda via llvm-dev <<a
            href="mailto:llvm-dev@lists.llvm.org" moz-do-not-send="true"
            class="moz-txt-link-freetext">llvm-dev@lists.llvm.org</a>>
          wrote:<br>
        </div>
        <blockquote class="gmail_quote" style="margin:0px 0px 0px
          0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">I'm
          in support of this proposal.<br>
          <br>
          I hit an unexpected preprocessor behavior in VS2017, forcing
          me to revert a patch that removed some repetitive code
          (D95532). The flag that fixes the issue
          (`/experimental:preprocessor`) is only present in Visual
          Studio 2017 version 15.8 and later. Raising the minimum
          supported version to VS2019 would allow us to enable
          `/Zc:preprocessor` and re-land the patch.<br>
          <br>
          Cheers,<br>
          Jan<br>
          <br>
          > On Nov 23, 2021, at 5:47 PM, Michael Kruse via llvm-dev
          <<a href="mailto:llvm-dev@lists.llvm.org" target="_blank"
            moz-do-not-send="true" class="moz-txt-link-freetext">llvm-dev@lists.llvm.org</a>>
          wrote:<br>
          > <br>
          > By our policy to support the last 2 major versions of VS,
          this is the<br>
          > right thing to do. Removing support for old compiler
          versions lessens<br>
          > the maintenance burden, e.g. when committing a change
          that happens to<br>
          > run a bug/missing feature of VS2017.<br>
          > <br>
          > If I am not mistaken, the value of the latest VS2019 is
          1929, not 1927 [1].<br>
          > <br>
          > Michael<br>
          > <br>
          > [1] <a
href="https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros?view=msvc-170"
            rel="noreferrer" target="_blank" moz-do-not-send="true"
            class="moz-txt-link-freetext">https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros?view=msvc-170</a><br>
          > <br>
          > Am Di., 23. Nov. 2021 um 05:56 Uhr schrieb Simon Pilgrim
          via llvm-dev<br>
          > <<a href="mailto:llvm-dev@lists.llvm.org"
            target="_blank" moz-do-not-send="true"
            class="moz-txt-link-freetext">llvm-dev@lists.llvm.org</a>>:<br>
          >> <br>
          >> Now that VS2022 is on general release, LLVM is
          expected to build on<br>
          >> VS2017, VS2019 and VS2022.<br>
          >> <br>
          >> What are people's thoughts on raising the minimum
          supported version to<br>
          >> latest VS2019 (_MSC_VER = 1927)? Customarily, we've
          only specifically<br>
          >> supported the latest 2 versions of Visual Studio,
          with older versions<br>
          >> being "allowed" (at your own risk) via the
          LLVM_FORCE_USE_OLD_TOOLCHAIN<br>
          >> cmake flag.<br>
          >> <br>
          >> I'm thinking we should either make the switch now, in
          plenty of time<br>
          >> before the next release of LLVM, or we postpone it
          until shortly after<br>
          >> the release branch is created (which I assume will be
          early 2022).<br>
          >> <br>
          >> For the record, I haven't so far noticed any issues
          with supporting<br>
          >> VS2017, VS2019 and VS2022 builds, so at this time I
          don't consider this<br>
          >> very urgent, just a general maintenance task -
          although somebody out<br>
          >> there may know of specific fixes in VS2019+ that
          could simplify LLVM<br>
          >> handling for MSVC etc.<br>
          >> <br>
          >> Cheers, Simon.<br>
          >> <br>
          >> _______________________________________________<br>
          >> LLVM Developers mailing list<br>
          >> <a href="mailto:llvm-dev@lists.llvm.org"
            target="_blank" moz-do-not-send="true"
            class="moz-txt-link-freetext">llvm-dev@lists.llvm.org</a><br>
          >> <a
            href="https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev"
            rel="noreferrer" target="_blank" moz-do-not-send="true"
            class="moz-txt-link-freetext">https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev</a><br>
          > _______________________________________________<br>
          > LLVM Developers mailing list<br>
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            moz-do-not-send="true" class="moz-txt-link-freetext">llvm-dev@lists.llvm.org</a><br>
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          <br>
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