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</o:shapelayout></xml><![endif]--></head><body lang=EN-IE link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Book Antiqua",serif'>I am wondering if there is some hidden option or mechanism in CLang that I can use to pre-process like ‘</span><span style='font-size:12.0pt;font-family:"Courier New"'>-E</span><span style='font-size:12.0pt;font-family:"Book Antiqua",serif'>’ or ‘</span><span style='font-size:12.0pt;font-family:"Courier New"'>-frewrite-includes</span><span style='font-size:12.0pt;font-family:"Book Antiqua",serif'>’, but which does not expand the headers from the system include directories?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Book Antiqua",serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Book Antiqua",serif'>There are often times when I would like this type of capability, so that I can create test-cases for reported bug, but have them remain valid with future revisions of the compiler and its supporting headers and libraries. It is not uncommon for a new version of a system header (ISO C, ISO C++, or our own extended headers) to have changes that are not 100% compatible with the results of the expanded result of an older version.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Book Antiqua",serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Book Antiqua",serif'>The headers belonging to the programmer and their source need to be expanded, but I would like to retain the unexpanded system headers, and in particular not expand the macros defined in a system header, and leave the system headers as ‘</span><span style='font-size:12.0pt;font-family:"Courier New"'>#include <<i>sysheadername</i>></span><span style='font-size:12.0pt;font-family:"Book Antiqua",serif'>’.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Book Antiqua",serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Book Antiqua",serif'>Thanks,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Book Antiqua",serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Book Antiqua",serif'> MartinO - Movidius Ltd.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Book Antiqua",serif'><o:p> </o:p></span></p></div></body></html>