<div dir="ltr"><div class="gmail_default" style="font-family:times new roman,serif;font-size:large">Filed <a href="https://gitlab.haskell.org/ghc/ghc/-/issues/25915">https://gitlab.haskell.org/ghc/ghc/-/issues/25915</a></div></div><br><div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr">On Tue, Apr 1, 2025 at 2:11 PM Andreas Klebinger via ghc-devs <<a href="mailto:ghc-devs@haskell.org">ghc-devs@haskell.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"><u></u>

  
    
  
  <div>
    <p>Looking at <a href="https://gitlab.haskell.org/ghc/ghc/-/issues/25011" target="_blank">https://gitlab.haskell.org/ghc/ghc/-/issues/25011</a> it
      seems the desire was to fail with a proper error when LLVM was not
      found at all.<br>
      <br>
      To me failing when the llvm version is too new seems like a
      unintended side effect of fixing the former. <br>
      <br>
      I agree that simply warning and trying anway is the better
      default. A ticket would be appreciated!<br>
    </p>
    <div>Am 01/04/2025 um 19:05 schrieb George
      Colpitts:<br>
    </div>
    <blockquote type="cite">
      
      <div dir="ltr">
        <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">I
          was trying to find out if it works but I ran into the problem
          I described. Yes, there were a few years where the latest
          version didn't work but in many years it did. ghc used to give
          a warning, this is an unsupported version but we'll try it
          anyways. I would like to return to that. </div>
        <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large"><br>
        </div>
        <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">In
          any case I believe ghc dev should test to see if it works and
          if so use it in HEAD. If it doesn't work than we should file a
          bug and fix it. In the past we got a few versions behind llvm.
          I think we want to be on the latest version available for each
          new release if possible. The earlier we look into this the
          more chance we have to succeed at that.</div>
      </div>
      <br>
      <div class="gmail_quote">
        <div dir="ltr" class="gmail_attr">On Tue, Apr 1, 2025 at 1:27 PM
          Brandon Allbery <<a href="mailto:allbery.b@gmail.com" target="_blank">allbery.b@gmail.com</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">
          <div dir="ltr">Have you demonstrated that it works? IIRC the
            current behavior is because some LLVM version (16, IIRC)
            didn't work with GHC (threw errors from opt, I think).</div>
          <br>
          <div class="gmail_quote">
            <div dir="ltr" class="gmail_attr">On Tue, Apr 1, 2025 at
              10:49 AM George Colpitts <<a href="mailto:george.colpitts@gmail.com" target="_blank">george.colpitts@gmail.com</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">
              <div dir="ltr">
                <div dir="ltr">
                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">llvm
                    20 is out but unlike in earlier versions of ghc
                    moving to it means you can no longer use llvm:</div>
                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large"><br>
                  </div>
                </div>
                <span style="font-family:"times new roman",serif;font-size:large">compiling<span class="gmail_default" style="font-family:"times new roman",serif;font-size:large">:</span></span>
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                              <div id="m_5825769736735240203m_7063798001418391762m_-5030501299994363526gmail-:1ca" style="font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:small;line-height:1.5;font-family:Arial,Helvetica,sans-serif;overflow:auto hidden">
                                <div>
                                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">ghc
                                    -fllvm hello.hs</div>
                                </div>
                              </div>
                            </div>
                          </div>
                        </div>
                      </div>
                    </div>
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                      <div style="border-left:none;padding:0px;display:flex;font-family:"Google Sans",Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:medium">
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                            <div id="m_5825769736735240203m_7063798001418391762m_-5030501299994363526gmail-:1cb" style="margin:8px 0px 0px;padding:0px;font-size:0.875rem;overflow-x:hidden">
                              <div id="m_5825769736735240203m_7063798001418391762m_-5030501299994363526gmail-:1ca" style="font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:small;line-height:1.5;font-family:Arial,Helvetica,sans-serif;overflow:auto hidden">
                                <div>
                                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">Loaded
                                    package environment from
                                    /Users/avie/.ghc/aarch64-darwin-9.12.2/environments/default</div>
                                </div>
                              </div>
                            </div>
                          </div>
                        </div>
                      </div>
                    </div>
                  </div>
                  <div>
                    <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">
                      <div style="border-left:none;padding:0px;display:flex;font-family:"Google Sans",Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:medium">
                        <div style="margin:0px;min-width:0px;padding:0px 0px 20px;width:auto">
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                            <div id="m_5825769736735240203m_7063798001418391762m_-5030501299994363526gmail-:1cb" style="margin:8px 0px 0px;padding:0px;font-size:0.875rem;overflow-x:hidden">
                              <div id="m_5825769736735240203m_7063798001418391762m_-5030501299994363526gmail-:1ca" style="font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:small;line-height:1.5;font-family:Arial,Helvetica,sans-serif;overflow:auto hidden">
                                <div>
                                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">[1
                                    of 2] Compiling Main             (
                                    hello.hs, hello.o )</div>
                                </div>
                              </div>
                            </div>
                          </div>
                        </div>
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                    </div>
                  </div>
                  <div>
                    <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">
                      <div style="border-left:none;padding:0px;display:flex;font-family:"Google Sans",Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:medium">
                        <div style="margin:0px;min-width:0px;padding:0px 0px 20px;width:auto">
                          <div>
                            <div id="m_5825769736735240203m_7063798001418391762m_-5030501299994363526gmail-:1cb" style="margin:8px 0px 0px;padding:0px;font-size:0.875rem;overflow-x:hidden">
                              <div id="m_5825769736735240203m_7063798001418391762m_-5030501299994363526gmail-:1ca" style="font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:small;line-height:1.5;font-family:Arial,Helvetica,sans-serif;overflow:auto hidden">
                                <div>
                                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large"><no
                                    location info>: error:
                                    [GHC-66599]</div>
                                </div>
                              </div>
                            </div>
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                    <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">
                      <div style="border-left:none;padding:0px;display:flex;font-family:"Google Sans",Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:medium">
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                            <div id="m_5825769736735240203m_7063798001418391762m_-5030501299994363526gmail-:1cb" style="margin:8px 0px 0px;padding:0px;font-size:0.875rem;overflow-x:hidden">
                              <div id="m_5825769736735240203m_7063798001418391762m_-5030501299994363526gmail-:1ca" style="font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:small;line-height:1.5;font-family:Arial,Helvetica,sans-serif;overflow:auto hidden">
                                <div>
                                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large"> 
                                      GHC was not configured with a
                                    supported LLVM toolchain</div>
                                </div>
                              </div>
                            </div>
                          </div>
                        </div>
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                    </div>
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                  <div>
                    <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">
                      <div style="border-left:none;padding:0px;display:flex;font-family:"Google Sans",Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:medium">
                        <div style="margin:0px;min-width:0px;padding:0px 0px 20px;width:auto">
                          <div>
                            <div id="m_5825769736735240203m_7063798001418391762m_-5030501299994363526gmail-:1cb" style="margin:8px 0px 0px;padding:0px;font-size:0.875rem;overflow-x:hidden">
                              <div id="m_5825769736735240203m_7063798001418391762m_-5030501299994363526gmail-:1ca" style="font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:small;line-height:1.5;font-family:Arial,Helvetica,sans-serif;overflow:auto hidden">
                                <div>
                                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large"> 
                                      Make sure you have installed LLVM
                                    between [13 and 20) and reinstall
                                    GHC to make -fllvm work</div>
                                </div>
                              </div>
                            </div>
                          </div>
                        </div>
                      </div>
                    </div>
                  </div>
                </blockquote>
                <div dir="ltr">
                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">
                    <div style="border-left:none;padding:0px;display:flex;font-family:"Google Sans",Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:medium">
                      <div style="margin:0px;min-width:0px;padding:0px 0px 20px;width:auto">
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                            <div id="m_5825769736735240203m_7063798001418391762m_-5030501299994363526gmail-:1ca" style="direction:ltr;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:small;line-height:1.5;font-family:Arial,Helvetica,sans-serif;overflow:auto hidden">
                              <div dir="ltr">
                                <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large"><br>
                                </div>
                                <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">from
                                  configure:</div>
                              </div>
                            </div>
                          </div>
                        </div>
                      </div>
                    </div>
                  </div>
                </div>
                <blockquote style="margin:0px 0px 0px 40px;border:none;padding:0px">
                  <div dir="ltr">
                    <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">
                      <div class="gmail_default">configure: We only
                        support llvm 13 upto 20 (non-inclusive) (found
                        20.1.1).</div>
                    </div>
                  </div>
                </blockquote>
                <div dir="ltr">
                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large"><br>
                  </div>
                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">Can
                    we move to llvm 20 on HEAD and can we revert to the
                    old behavior on ghc 9.12.3?</div>
                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large"><br>
                  </div>
                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">Should
                    I file an ER?</div>
                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large"><br>
                  </div>
                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large">Thanks</div>
                  <div class="gmail_default" style="font-family:"times new roman",serif;font-size:large"><br>
                  </div>
                </div>
              </div>
              _______________________________________________<br>
              ghc-devs mailing list<br>
              <a href="mailto:ghc-devs@haskell.org" target="_blank">ghc-devs@haskell.org</a><br>
              <a href="http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs" rel="noreferrer" target="_blank">http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs</a><br>
            </blockquote>
          </div>
          <div><br clear="all">
          </div>
          <div><br>
          </div>
          <span class="gmail_signature_prefix">-- </span><br>
          <div dir="ltr" class="gmail_signature">
            <div dir="ltr">
              <div>
                <div dir="ltr">
                  <div>brandon s allbery kf8nh</div>
                  <div><a href="mailto:allbery.b@gmail.com" target="_blank">allbery.b@gmail.com</a></div>
                </div>
              </div>
            </div>
          </div>
        </blockquote>
      </div>
      <br>
      <fieldset></fieldset>
      <pre>_______________________________________________
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<a href="mailto:ghc-devs@haskell.org" target="_blank">ghc-devs@haskell.org</a>
<a href="http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs" target="_blank">http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs</a>
</pre>
    </blockquote>
  </div>

_______________________________________________<br>
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</blockquote></div>