How to switch off specific warnings in Qt Creator
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Folks,
I am getting lots of depricated warnings (I cannot upgrade to a newer version of Qt BTW, so, for me, this is not going to be a solution I have seen suggested elsewhere). After doing loads of trawling around, the method seems to be to add to your .pro file:
QMAKE_CXXFLAGS_WARN_OFF -= -Wdeprecated-copyHowever, this makes no an iota of difference.
This is an example of a full warning message:
/path/qtransform.h:376: warning: implicitly-declared ‘QTransform::QTransform(const QTransform&)’ is deprecated [-Wdeprecated-copy] In file included from /path//QtGui/qbrush.h:43, from /path//qpalette.h:39, from /path//qwidget.h:41, from /path//QWidget:1, from ../PI03SW05/crc.h:5, from ../PI03SW05/crc.cpp:1: /path/qtransform.h: In function ‘QTransform operator*(const QTransform&, qreal)’: /path/qtransform.h:376:17: warning: implicitly-declared ‘QTransform::QTransform(const QTransform&)’ is deprecated [-Wdeprecated-copy] 376 | { QTransform t(a); t *= n; return t; } | ^ /path/qtransform.h:121:17: note: because ‘QTransform’ has user-provided ‘QTransform& QTransform::operator=(const QTransform&)’ 121 | QTransform &operator=(const QTransform &);Anyone know what I am doing wrong here and (with explicit instructions) how to fix this please? Am using 5.6.3 on Linux FWIW.
Thanks :)
@DiBosco said in How to switch off specific warnings in Qt Creator:
However, this makes no an iota of difference.
According to https://forum.qt.io/post/649283 you should:
Use
CONFIG += warn_offin your .pro file to disable warnings. This will make sure the compiler is called with all the flags set inQMAKE_CXXFLAGS_WARN_OFF(which should be automatically set by the default mkspecs, so usually no reason to change it). -
@DiBosco
Did you actually try it though? I read the answer as indicating/suggesting thatCONFIG += warn_offis required to makeQMAKE_CXXFLAGS_WARN_OFFbe taken into account? The OP there seemed to say same as you: settingQMAKE_CXXFLAGS_WARN_OFFalone did not have any effect.Try it to see if you can tell it makes a difference? Check the actual options being passed to the gcc in each case? Figure how to make
QMAKE_CXXFLAGS_WARN_OFFactually affect things if it does it right from theCONFIGstatement but not in your case? -
@DiBosco
Did you actually try it though? I read the answer as indicating/suggesting thatCONFIG += warn_offis required to makeQMAKE_CXXFLAGS_WARN_OFFbe taken into account? The OP there seemed to say same as you: settingQMAKE_CXXFLAGS_WARN_OFFalone did not have any effect.Try it to see if you can tell it makes a difference? Check the actual options being passed to the gcc in each case? Figure how to make
QMAKE_CXXFLAGS_WARN_OFFactually affect things if it does it right from theCONFIGstatement but not in your case? -
@JonB Yes, that's how I know it suppresses all warnings :)
If I put this in my .pro file:
CONFIG += warn_off QMAKE_CXXFLAGS_WARN_OFF -= -Wdeprecated-copyNo warnings at all. If I take out the:
CONFIG += warn_offline then all warnings are present.
@DiBosco
I already suggested: you ought find out why (apparently, according to you and the other poster) that withoutCONFIG += warn_offsettingQMAKE_CXXFLAGS_WARN_OFF -= -Wdeprecated-copyhas no effect. Then maybe you will be able to removeCONFIGand know what you have to do to makeQMAKE_CXXFLAGS_WARN_OFF -= -Wdeprecated-copywork on its own.Not that I know anything about this, but I would guess that
QMAKE_CXXFLAGS_WARN_OFFis only used at all if you haveCONFIG += warn_off, i.e. the latter "activates" the former's flags to be used. Without that configurationQMAKE_CXXFLAGS_WARN_OFFis not passed to compiler. If you want-Wdeprecated-copyin other circumstances than with all other warnings turned off I would presume you should use another variable which is always passed to compiler. Something likeQMAKE_CXXFLAGS? Does that satisfy you? -
@DiBosco
I already suggested: you ought find out why (apparently, according to you and the other poster) that withoutCONFIG += warn_offsettingQMAKE_CXXFLAGS_WARN_OFF -= -Wdeprecated-copyhas no effect. Then maybe you will be able to removeCONFIGand know what you have to do to makeQMAKE_CXXFLAGS_WARN_OFF -= -Wdeprecated-copywork on its own.Not that I know anything about this, but I would guess that
QMAKE_CXXFLAGS_WARN_OFFis only used at all if you haveCONFIG += warn_off, i.e. the latter "activates" the former's flags to be used. Without that configurationQMAKE_CXXFLAGS_WARN_OFFis not passed to compiler. If you want-Wdeprecated-copyin other circumstances than with all other warnings turned off I would presume you should use another variable which is always passed to compiler. Something likeQMAKE_CXXFLAGS? Does that satisfy you? -
I'm not sure I've made it clear that with
CONFIG += warn_offAll warnings go. So, for example, unused variables no long show up (which I want to see).
I want all deprecated warnings to go, but I want to see other types of warning.
@DiBosco said in How to switch off specific warnings in Qt Creator:
I'm not sure I've made it clear that with
CONFIG += warn_offAll warnings go. So, for example, unused variables no long show up (which I want to see).
I want all deprecated warnings to go, but I want to see other types of warning.
PS Trying to find out what I ought to do is what I'm doing here. I spent absolutely ages trawling round various sites such as here and Stack Overflow to no avail.
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I'm not sure I've made it clear that with
CONFIG += warn_offAll warnings go. So, for example, unused variables no long show up (which I want to see).
I want all deprecated warnings to go, but I want to see other types of warning.
@DiBosco said in How to switch off specific warnings in Qt Creator:
All warnings go. So, for example, unused variables no long show up (which I want to see).
I want all deprecated warnings to go, but I want to see other types of warning.
I know this. And I suggested why
QMAKE_CXXFLAGS_WARN_OFFprobably has no effect and precisely what you should do, which you apparently have not tried..... -
@DiBosco said in How to switch off specific warnings in Qt Creator:
All warnings go. So, for example, unused variables no long show up (which I want to see).
I want all deprecated warnings to go, but I want to see other types of warning.
I know this. And I suggested why
QMAKE_CXXFLAGS_WARN_OFFprobably has no effect and precisely what you should do, which you apparently have not tried.....I think I'm missing something here because I said a few posts up I tried:
CONFIG += warn_off QMAKE_CXXFLAGS_WARN_OFF -= -Wdeprecated-copySo I have tried QMAKE_CXXFLAGS_WARN_OFF. Sorry if I'm being slow here, but if that's not what you mean I need something more explicit to try.
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@DiBosco Have you already seen https://stackoverflow.com/questions/22129383/removing-unused-parameters-warning-in-qtcreator ?
For your case, it would be:
QMAKE_CXXFLAGS_WARN_ON += -Wno-deprecated-copyRegards
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I think I'm missing something here because I said a few posts up I tried:
CONFIG += warn_off QMAKE_CXXFLAGS_WARN_OFF -= -Wdeprecated-copySo I have tried QMAKE_CXXFLAGS_WARN_OFF. Sorry if I'm being slow here, but if that's not what you mean I need something more explicit to try.
@DiBosco
:)- Forget about
CONFIG ..., remove it. - Forget about
QMAKE_CXXFLAGS_WARN_OFF ..., remove it. - Try this:
If you want
-Wdeprecated-copyin other circumstances than with all other warnings turned off I would presume you should use another variable which is always passed to compiler. Something likeQMAKE_CXXFLAGS? Does that satisfy you?I cannot be sure which one to use, but what happens if you add a line reading:
QMAKE_CXXFLAGS -= -Wdeprecated-copyIf that does not work we (you!) need to understand what is adding
-Wdeprecated-copyon the gcc compiler line (I asked you to look at the actual line being generated, does it have that option?) and then presumably something likeTHE_MACRO_WHICH_ADDED_IT -= -Wdeprecated-copyto remove it?P.S.
Since @aha_1980 has just chimed in to say there is aQMAKE_CXXFLAGS_WARN_ONand a-Wno-deprecated-copywhich can be added you should try that. If by any chance that does not work you might have to put it onQMAKE_CXXFLAGS, but try what he says first. - Forget about
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@DiBosco Have you already seen https://stackoverflow.com/questions/22129383/removing-unused-parameters-warning-in-qtcreator ?
For your case, it would be:
QMAKE_CXXFLAGS_WARN_ON += -Wno-deprecated-copyRegards
@aha_1980 said in How to switch off specific warnings in Qt Creator:
@DiBosco Have you already seen https://stackoverflow.com/questions/22129383/removing-unused-parameters-warning-in-qtcreator ?
For your case, it would be:
QMAKE_CXXFLAGS_WARN_ON += -Wno-deprecated-copyRegards
Ah, yes I had seen that. The English in the most upticked reply just made me go "What?". Just could not understand what they were saying, but I had tried:
QMAKE_CXXFLAGS_WARN_ON += -Wdeprecated-copy
Thinking why on earth would putting the warning on make it disappear, but out of desperation I gave it a go. Had I realised it needed -Wno-deprecated-copy, not -Wdeprecated-copy I'd've been fine hours ago.
Many thanks for that, now doing just what I want.
Also @JonB Thanks for your help too.
