<html><head><meta http-equiv="Content-Type" content="text/html charset=windows-1252"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">On Jan 9, 2014, at 2:20 PM, Richard Smith <<a href="mailto:richard@metafoo.co.uk">richard@metafoo.co.uk</a>> wrote:<br><div><br class="Apple-interchange-newline"><blockquote type="cite"><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Thu, Jan 9, 2014 at 7:25 AM, Alp Toker <span dir="ltr"><<a href="mailto:alp@nuanti.com" target="_blank">alp@nuanti.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0px 0px 0px 0.8ex; border-left-width: 1px; border-left-color: rgb(204, 204, 204); border-left-style: solid; padding-left: 1ex; position: static; z-index: auto;"> </blockquote><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> It's not fair on the user or the system header maintainers to bring up unexpected errors with this flag.<br>
</blockquote><div><br></div><div>I don't think this is clear. If the code in the system header is ill-formed, I would expect the system header maintainers to be *grateful* that we flag it as an error and not just as a warning. But I'll wait to hear what they have to say about that.</div></div></div></div></blockquote><div><br></div><div>A few points, in no particular order:</div><div><br></div></div><div>* If we have ill-formed code in system headers, I would expect it to fail to compile whether the user specifies -<span style="font-family: LucidaGrande;">Wsystem-headers </span>or not.</div><div><br></div><div>* If a user has a clean build, and then rebuilds with -<font face="LucidaGrande">Wsystem-headers, I would expect to get warnings - not errors. [ Isn’t that what PR</font>18327 is all about? ]</div><div><br></div><div><span style="font-family: LucidaGrande;">* There are some “interesting” language features which are only enabled for system headers, and cause warnings if used in user code.</span></div><div><font face="LucidaGrande">[ User-defined suffixes that do not start with an underscore, for example. ]</font></div><div><br></div><div>— Marshall</div></body></html>