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</o:shapelayout></xml><![endif]--></head><body lang=EN-IE link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'>I long while back, I added a static function to my ‘Subtarget’ implementation that allows me to pass all of the ‘-cc1’ arguments from CLang to the LLVM backend.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'>The reason I added this was because I would routinely get examples of “bugs” from developers that consisted of only assembly code, and no information about how the compiler was invoked, nor the C or C++ source.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'>So I partially addressed this by placing all the ‘-cc1’ options into a large comment section at the end of each generated assembly file to help with my diagnostics, and this information is passed from CLang to LLVM using this call.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'>But this breaks the natural decoupling of the CLang front-end and the LLVM backend, so that other clients of ‘libclang’ implicitly have this weak extern reference.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'>Using the GCC or CLang compilers, the use of weak-externs is not a problem so my additional function does not need to be linked into the image, but with VC++ it is a problem as there is no real equivalent that I know of for weak-extern; and this means that I cannot build many of the additional CLang utilities unless I also link them against the back-end, which is not the right thing to do.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'>I think that the right solution would be to decouple how I pass this information from CLang to LLVM, and I would like to seek advice from the community on how I might better implement this requirement. Or if there is an existing mechanism I could use to do this.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'>Thanks in advance,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'> MartinO<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:12.0pt;font-family:"Book Antiqua","serif"'><o:p> </o:p></span></p></div></body></html>