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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Hmm, so it does: HSOpts.UseLibcxx. My mistake.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>-Brian<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> jordan_rose@apple.com [mailto:jordan_rose@apple.com] <br><b>Sent:</b> Friday, November 18, 2016 12:59 PM<br><b>To:</b> Brian Cain <bcain@codeaurora.org><br><b>Cc:</b> llvm-dev <llvm-dev@lists.llvm.org><br><b>Subject:</b> Re: [llvm-dev] "-stdlib=libc++" applied to CMAKE_CXX_FLAGS<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Doesn't this control search paths as well? It's only because you're specifying -nostdinc++ that it's going unused for you.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Jordan<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal>On Nov 18, 2016, at 10:50, Brian Cain <<a href="mailto:bcain@codeaurora.org">bcain@codeaurora.org</a>> wrote:<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Jordan,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Waaay back in 2014 you added “append_if(CXX_SUPPORTS_STDLIB "-stdlib=libc++" CMAKE_CXX_FLAGS)” to HandleLLVMStdlib.cmake and I’m asking if it might’ve been in error. I’ll submit a review to delete the CMAKE_CXX_FLAGS unless you think it still makes sense.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>-Brian<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><div><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span class=apple-converted-space><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>llvm-dev [<a href="mailto:llvm-dev-bounces@lists.llvm.org"><span style='color:#954F72'>mailto:llvm-dev-bounces@lists.llvm.org</span></a>]<span class=apple-converted-space> </span><b>On Behalf Of<span class=apple-converted-space> </span></b>Brian Cain via llvm-dev<br><b>Sent:</b><span class=apple-converted-space> </span>Thursday, November 17, 2016 5:10 PM<br><b>To:</b><span class=apple-converted-space> </span>'llvm-dev' <<a href="mailto:llvm-dev@lists.llvm.org"><span style='color:#954F72'>llvm-dev@lists.llvm.org</span></a>><br><b>Subject:</b><span class=apple-converted-space> </span>[llvm-dev] "-stdlib=libc++" applied to CMAKE_CXX_FLAGS<o:p></o:p></span></p></div></div></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>llvm/cmake/modules/HandleLLVMStdlib.cmake specifies “-stdlib=libc++” for CMAKE_CXX_FLAGS when LLVM_ENABLE_LIBCXX and CXX_SUPPORTS_STDLIB. From what I can see this is a flag intended for the linker and not the compiler.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>I’d like to submit a change to delete CMAKE_CXX_FLAGS from this append() but I wanted to check in with the list to see if that makes sense or if there are other contexts for which “stdlib=libc++” might be used.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>If I specify “-nostdinc++”, “-stdlib=libc++” doesn’t get consumed and clang emits a warning.<span class=apple-converted-space> </span><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>$ clang++ -nostdinc++ -stdlib=libc++ -o main.o -c main.cpp<o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>clang-4.0: warning: argument unused during compilation: '-stdlib=libc++' [-Wunused-command-line-argument]<o:p></o:p></span></p></div></div></blockquote></div><p class=MsoNormal><o:p> </o:p></p></div></body></html>