<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On May 22, 2018, at 4:29 PM, Shoaib Meenai <<a href="mailto:smeenai@fb.com" class="">smeenai@fb.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="WordSection1" style="page: WordSection1; caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">Based on all the discussion so far, I think the consensus is that we don't want to relax -Wformat by default, but an additional relaxed option would be fine. That works for me (where I can just switch my codebases to use the new warning option), but it wouldn't handle JF Bastien's use case, so he would still want to pursue the relaxations specific to Apple platforms.<o:p class=""></o:p></div><div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div><div style="margin: 0in 0in 0.0001pt; font-size: 11pt; font-family: Calibri, sans-serif;" class="">Does that sound reasonable to everyone? I'm not going to be able to get to the -Wformat relaxation myself immediately, since I have more pressing work right now, but it sounds like Apple will be doing their own thing anyway, so I wouldn't be blocking them.</div></div></div></blockquote><div><br class=""></div><div>Sounds good, on our side we’re happy with the patch in D42933, so we’ll move the discussion there.</div><div>Thanks for pursuing the discussion on cfe-dev!</div><div><br class=""></div><div><br class=""></div><blockquote type="cite" class=""><div class=""><div class="WordSection1" style="page: WordSection1; caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><div style="border-style: solid none none; border-top-width: 1pt; border-top-color: rgb(181, 196, 223); padding: 3pt 0in 0in;" class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><b class=""><span style="font-size: 12pt;" class="">From:<span class="Apple-converted-space"> </span></span></b><span style="font-size: 12pt;" class="">cfe-dev <<a href="mailto:cfe-dev-bounces@lists.llvm.org" class="">cfe-dev-bounces@lists.llvm.org</a>> on behalf of cfe-dev <<a href="mailto:cfe-dev@lists.llvm.org" class="">cfe-dev@lists.llvm.org</a>><br class=""><b class="">Reply-To:<span class="Apple-converted-space"> </span></b>Aaron Ballman <<a href="mailto:aaron@aaronballman.com" class="">aaron@aaronballman.com</a>><br class=""><b class="">Date:<span class="Apple-converted-space"> </span></b>Tuesday, May 22, 2018 at 9:11 AM<br class=""><b class="">To:<span class="Apple-converted-space"> </span></b>Hans Wennborg <<a href="mailto:hans@chromium.org" class="">hans@chromium.org</a>><br class=""><b class="">Cc:<span class="Apple-converted-space"> </span></b>cfe-dev <<a href="mailto:cfe-dev@lists.llvm.org" class="">cfe-dev@lists.llvm.org</a>><br class=""><b class="">Subject:<span class="Apple-converted-space"> </span></b>Re: [cfe-dev] Relaxing format specifier checks<o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">On Tue, May 22, 2018 at 5:40 AM, Hans Wennborg via cfe-dev<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><<a href="mailto:cfe-dev@lists.llvm.org" style="color: purple; text-decoration: underline;" class="">cfe-dev@lists.llvm.org</a>> wrote:<o:p class=""></o:p></div></div><blockquote id="MAC_OUTLOOK_ATTRIBUTION_BLOCKQUOTE" style="border-style: none none none solid; border-left-width: 4.5pt; border-left-color: rgb(181, 196, 223); padding: 0in 0in 0in 4pt; margin-left: 3.75pt; margin-right: 0in;" class=""><blockquote id="MAC_OUTLOOK_ATTRIBUTION_BLOCKQUOTE" style="border-style: none none none solid; border-left-width: 4.5pt; border-left-color: rgb(181, 196, 223); padding: 0in 0in 0in 4pt; margin-left: 3.75pt; margin-right: 0in;" class=""><blockquote id="MAC_OUTLOOK_ATTRIBUTION_BLOCKQUOTE" style="border-style: none none none solid; border-left-width: 4.5pt; border-left-color: rgb(181, 196, 223); padding: 0in 0in 0in 4pt; margin-left: 3.75pt; margin-right: 0in;" class=""><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">I still maintain that the warning discussed in D42933 is correct. The<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">problem to be solved is how to "relax" the warning for those who don't<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">think their code needs to be checked that strictly.<o:p class=""></o:p></div></div></blockquote><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">I’m not sure I get your point of view. Is it that you don’t think platforms can offer guarantees beyond what the language mandates; you don’t think Darwin offers said guarantees; you think the guarantee Darwin offers is bogus; or you think that in instances where platforms offer these supplemental guarantees the compiler should warn regardless? Or is it something else?<o:p class=""></o:p></div></div></blockquote><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">Yes, I think the compiler should warn regardless because the code is<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">still technically incorrect, and not just in a<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">trailing-comma-after-last-enumerator way, but in a way I think many<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">users care about. I think users expect -Wformat to help them get the<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">format specifiers right as per the spec.<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div></div><blockquote id="MAC_OUTLOOK_ATTRIBUTION_BLOCKQUOTE" style="border-style: none none none solid; border-left-width: 4.5pt; border-left-color: rgb(181, 196, 223); padding: 0in 0in 0in 4pt; margin-left: 3.75pt; margin-right: 0in;" class=""><blockquote id="MAC_OUTLOOK_ATTRIBUTION_BLOCKQUOTE" style="border-style: none none none solid; border-left-width: 4.5pt; border-left-color: rgb(181, 196, 223); padding: 0in 0in 0in 4pt; margin-left: 3.75pt; margin-right: 0in;" class=""><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">But the original problem is that Clang warns on printing NSInteger<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">with %zd, and having a -Wformat-relaxed or whatever would solve that<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">for users who don't want to fix their code. What else do you mean<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">needs fixing?<o:p class=""></o:p></div></div></blockquote><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">I need to understand the answer to my question above before we can really discuss this, but basically my POV is that a warning about something a platform guarantees will never be an issue shouldn’t be on by default at -Wall, especially if it’s been show to be quite noisy in real-world code. You can opt-in to more warnings with -Wpedantic or other sub-pedantic flags, but you shouldn’t get it out of -Wall.<o:p class=""></o:p></div></div></blockquote><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">My point of view is that warning about these details is valuable<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">enough to be on by default. I would see it as a great regression if<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">Clang stopped warning about printing long with %d on Windows for<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">example --- even though the target guarantees that it works and will<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">never be an issue. And I also see the value in letting users who don't<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">care turn it off.<o:p class=""></o:p></div></div></blockquote><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">+1<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">~Aaron<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">_______________________________________________<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class="">cfe-dev mailing list<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><a href="mailto:cfe-dev@lists.llvm.org" style="color: purple; text-decoration: underline;" class="">cfe-dev@lists.llvm.org</a><o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt 0.5in; font-size: 11pt; font-family: Calibri, sans-serif;" class=""><a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.llvm.org_cgi-2Dbin_mailman_listinfo_cfe-2Ddev&d=DwIGaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=0dYR5xovLPt1wdh6qksdtr2KWUuJOTxxssOpCBqh1nU&s=Q3ZVP9aCVOpfSd2uhYH1xfg0kD3Fr-LnVkBWVlakXjU&e=" style="color: purple; text-decoration: underline;" class="">https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.llvm.org_cgi-2Dbin_mailman_listinfo_cfe-2Ddev&d=DwIGaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=0dYR5xovLPt1wdh6qksdtr2KWUuJOTxxssOpCBqh1nU&s=Q3ZVP9aCVOpfSd2uhYH1xfg0kD3Fr-LnVkBWVlakXjU&e=</a></div></div></div></div></blockquote></div><br class=""></body></html>