Re: C++11, 'throw', etc.
Larry Gritz <[email protected]> Thu, 10 Aug 2017 10:18:31 -0700
| Newsgroups | gmane.comp.video.openexr.devel |
|---|---|
| Message-ID | <[email protected]> |
--===============5452419802731800745== Content-Type: multipart/alternative; boundary="Apple-Mail=_F263BD48-53DB-47E1-85AA-CFC41C28F038" --Apple-Mail=_F263BD48-53DB-47E1-85AA-CFC41C28F038 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii Ugh, so it's worse than I thought. I suppose I'm willing to fix and submit a patch to address this. Do I need to put in the proper macros to make it compile on everything = from C++03 through 17? Does anybody want to argue for continuing to = maintain C++03 compatibility for future OpenEXR releases, or is it = finally time (six years after the C++ standard and 2+ years after = VFXPlatform) to raise the floor to C++11? -- lg > On Aug 9, 2017, at 11:38 PM, Werner Benger <[email protected]> wrote: >=20 > It should be noted that dynamic expressions are actually forbidden in = C++17, so OpenEXR does no longer compile with GCC 7.1 when std C++17 is = enabled. The highest C++ version that can be used to compile it is = C++14, where it's still just a warning, while in C++17 it's an error. It = would be good to have OpenEXR at least compilable in C++17. Major C++ = libraries such as QT are using C++11 nowadays, so it seems pretty safe = to go beyond C++03 for modern applications, a lot of things are indeed = much easier. >=20 > Werner >=20 >=20 > On 10.08.2017 00:20, Larry Gritz wrote: >> In a test compile with gcc 7, I get lots of errors of the following = ilk: >>=20 >> /home/travis/build/lgritz/openexr/IlmBase/Imath/ImathVec.h:228:34: = warning: dynamic exception specifications are deprecated in C++11 = [-Wdeprecated] >> const Vec2 & normalizeExc () throw (IEX_NAMESPACE::MathExc); >> ^~~~~ >>=20 >> I can disable this particular warning, of course, but it's worth = noting that the OpenEXR code base is not C++11 compliant. But in = addition to using some C++03 idioms that are deprecated in C++11, = perhaps more importantly, the code is not taking advantage of new = features such as move semantics, constexpr, nothrow, and others. For the = Imath classes especially, using some of these may actually confer a = performance benefit. >>=20 >> I feel kind of bad pointing this out while not really having the time = at the moment to code up and submit an actual patch myself, but I = thought I'd at least open the topic and see where the community stands = on the issue of how and when to upgrade to C++11 and if it's important = for modern OpenEXR to continue to support C++03. For point of reference, = the VFX Reference Platform [http://www.vfxplatform.com/] dictated C++11 = for 2016 and 2017, and will be C++14 for 2018. >>=20 >> -- lg >>=20 >> -- >> Larry Gritz >> [email protected] >>=20 >>=20 >>=20 >>=20 >>=20 >> _______________________________________________ >> Openexr-devel mailing list >> [email protected] >> https://lists.nongnu.org/mailman/listinfo/openexr-devel >=20 > --=20 > = __________________________________________________________________________= _ > Dr. Werner Benger Visualization Research > Center for Computation & Technology at Louisiana State University = (CCT/LSU) > 2019 Digital Media Center, Baton Rouge, Louisiana 70803 > Tel.: +1 225 578 4809 Fax.: +1 225 578-5362 >=20 >=20 > _______________________________________________ > Openexr-devel mailing list > [email protected] > https://lists.nongnu.org/mailman/listinfo/openexr-devel -- Larry Gritz [email protected] --Apple-Mail=_F263BD48-53DB-47E1-85AA-CFC41C28F038 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=us-ascii <html><head><meta http-equiv=3D"Content-Type" content=3D"text/html = charset=3Dus-ascii"></head><body style=3D"word-wrap: break-word; = -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" = class=3D"">Ugh, so it's worse than I thought.<div class=3D""><br = class=3D""></div><div class=3D"">I suppose I'm willing to fix and submit = a patch to address this.</div><div class=3D""><br class=3D""></div><div = class=3D"">Do I need to put in the proper macros to make it compile on = everything from C++03 through 17? Does anybody want to argue for = continuing to maintain C++03 compatibility for future OpenEXR releases, = or is it finally time (six years after the C++ standard and 2+ years = after VFXPlatform) to raise the floor to C++11?</div><div class=3D""><br = class=3D""></div><div class=3D""><span class=3D"Apple-tab-span" = style=3D"white-space:pre"> </span>-- lg</div><div class=3D""><br = class=3D""></div><div class=3D""><br class=3D""><div><blockquote = type=3D"cite" class=3D""><div class=3D"">On Aug 9, 2017, at 11:38 PM, = Werner Benger <<a href=3D"mailto:[email protected]" = class=3D"">[email protected]</a>> wrote:</div><br = class=3D"Apple-interchange-newline"><div class=3D""><div class=3D"">It = should be noted that dynamic expressions are actually forbidden in = C++17, so OpenEXR does no longer compile with GCC 7.1 when std C++17 is = enabled. The highest C++ version that can be used to compile it is = C++14, where it's still just a warning, while in C++17 it's an error. It = would be good to have OpenEXR at least compilable in C++17. Major = C++ libraries such as QT are using C++11 nowadays, so it seems pretty = safe to go beyond C++03 for modern applications, a lot of things are = indeed much easier.<br class=3D""><br class=3D""> = Werner<br class=3D""><br class=3D""><br = class=3D"">On 10.08.2017 00:20, Larry Gritz wrote:<br = class=3D""><blockquote type=3D"cite" class=3D"">In a test compile with = gcc 7, I get lots of errors of the following ilk:<br class=3D""><br = class=3D"">/home/travis/build/lgritz/openexr/IlmBase/Imath/ImathVec.h:228:= 34: warning: dynamic exception specifications are deprecated in C++11 = [-Wdeprecated]<br class=3D""> const Vec2 = & normalizeExc () throw (IEX_NAMESPACE::MathExc);<br class=3D""> = &n= bsp; &nbs= p; ^~~~~<br = class=3D""><br class=3D"">I can disable this particular warning, of = course, but it's worth noting that the OpenEXR code base is not C++11 = compliant. But in addition to using some C++03 idioms that are = deprecated in C++11, perhaps more importantly, the code is not taking = advantage of new features such as move semantics, constexpr, nothrow, = and others. For the Imath classes especially, using some of these may = actually confer a performance benefit.<br class=3D""><br class=3D"">I = feel kind of bad pointing this out while not really having the time at = the moment to code up and submit an actual patch myself, but I thought = I'd at least open the topic and see where the community stands on the = issue of how and when to upgrade to C++11 and if it's important for = modern OpenEXR to continue to support C++03. For point of reference, the = VFX Reference Platform [<a href=3D"http://www.vfxplatform.com/" = class=3D"">http://www.vfxplatform.com/</a>] dictated C++11 for 2016 and = 2017, and will be C++14 for 2018.<br class=3D""><br class=3D""><span = class=3D"Apple-tab-span" style=3D"white-space:pre"> </span>-- lg<br = class=3D""><br class=3D"">--<br class=3D"">Larry Gritz<br class=3D""><a = href=3D"mailto:[email protected]" class=3D"">[email protected]</a><br = class=3D""><br class=3D""><br class=3D""><br class=3D""><br class=3D""><br= class=3D"">_______________________________________________<br = class=3D"">Openexr-devel mailing list<br = class=3D"">[email protected]<br = class=3D"">https://lists.nongnu.org/mailman/listinfo/openexr-devel<br = class=3D""></blockquote><br class=3D"">-- <br = class=3D"">_______________________________________________________________= ____________<br class=3D"">Dr. Werner Benger = &n= bsp; Visualization Research<br class=3D"">Center for = Computation & Technology at Louisiana State University (CCT/LSU)<br = class=3D"">2019 Digital Media Center, Baton Rouge, Louisiana = 70803<br class=3D"">Tel.: +1 225 578 4809 = &n= bsp; Fax.: +1 = 225 578-5362<br class=3D""><br class=3D""><br = class=3D"">_______________________________________________<br = class=3D"">Openexr-devel mailing list<br class=3D""><a = href=3D"mailto:[email protected]" = class=3D"">[email protected]</a><br = class=3D"">https://lists.nongnu.org/mailman/listinfo/openexr-devel<br = class=3D""></div></div></blockquote></div><br class=3D""><div class=3D""> <div style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; = -webkit-line-break: after-white-space;" class=3D""><div style=3D"color: = rgb(0, 0, 0); font-family: Helvetica; font-size: 14px; 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;">--</div><div style=3D"color: rgb(0, 0, 0); font-family: Helvetica; = font-size: 14px; 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;">Larry = Gritz</div><div style=3D"color: rgb(0, 0, 0); font-family: Helvetica; = font-size: 14px; 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;"><a = href=3D"mailto:[email protected]" = class=3D"">[email protected]</a></div><div style=3D"color: rgb(0, 0, 0); = font-family: Helvetica; font-size: 14px; 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;" class=3D""><br= class=3D""></div><br class=3D"Apple-interchange-newline"></div><br = class=3D"Apple-interchange-newline"> </div> <br class=3D""></div></body></html>= --Apple-Mail=_F263BD48-53DB-47E1-85AA-CFC41C28F038-- --===============5452419802731800745== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Openexr-devel mailing list [email protected] https://lists.nongnu.org/mailman/listinfo/openexr-devel --===============5452419802731800745==--