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</o:shapelayout></xml><![endif]--></head><body lang=EN-IE link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:black;mso-fareast-language:EN-US'>Sounds like the perfect solution - no opportunity for error :-)<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:black;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:black;mso-fareast-language:EN-US'>Thanks Eric,<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:black;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:black;mso-fareast-language:EN-US'> MartinO<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Book Antiqua",serif;color:#943634;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'> Eric Fiselier [mailto:eric@efcs.ca] <br><b>Sent:</b> 07 May 2017 20:59<br><b>To:</b> Martin J. O'Riordan <martin.oriordan@movidius.com><br><b>Cc:</b> clang developer list <cfe-dev@lists.llvm.org>; Marshall Clow <mclow.lists@gmail.com>; Duncan P. N. Exon Smith <dexonsmith@apple.com>; Ed Maste <emaste@freebsd.org>; Anton Korobeynikov <anton@korobeynikov.info><br><b>Subject:</b> Re: [RFC] Possible ABI break for libc++ built with -fno-rtti and -D_LIBCPP_BUILD_STATIC<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><div><div><p class=MsoNormal>On Sun, May 7, 2017 at 7:50 AM, Martin J. O'Riordan <<a href="mailto:martin.oriordan@movidius.com" target="_blank">martin.oriordan@movidius.com</a>> wrote:<o:p></o:p></p><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-family:"Book Antiqua",serif;color:black'>Hi Eric,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-family:"Book Antiqua",serif;color:black'>In the email I sent on the 27<sup>th</sup> April (“[LibC++] Bug in implementation of 'std::shared_ptr'”), the problem I was seeing was:</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-family:"Book Antiqua",serif;color:black'> o LibC++ library built with -DLIBCXX_ENABLE_RTTI=ON and -D_LIBCPP_BUILD_STATIC.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-family:"Book Antiqua",serif;color:black'> o User code compiled with ‘-fno-rtti -D_LIBCPP_BUILD_STATIC’.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-family:"Book Antiqua",serif;color:black'>Having ‘_LIBCPP_BUILD_STATIC’ defined by both the library builder and the library user was where it broke. I removed ‘-D_LIBCPP_BUILD_STATIC’ from the user and it worked. But I wasn’t building the static library with RTTI disabled because it is stated as an unsupported configuration.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-family:"Book Antiqua",serif;color:black'>So are you advising that with the proposed fix, that I should revert to defining ‘_LIBCPP_BUILD_STATIC’ as the user?</span><o:p></o:p></p></div></div></blockquote><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>`_LIBCPP_BUILD_STATIC` has been removed entirely by the change. It fixes your bug by making the vtable consistent across all configurations.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> /Eric<o:p></o:p></p></div></div></div></div></div></body></html>