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How to prevent MinGW Qt 5.9 kit from adding -std=gnu++11/14/1z to compile flags?
krzaq last edited by
In the previous versions (up to 5.8) all I had to do was add the following to the
CONFIG -= c++11 CONFIG -= c++14
Then, I'd be free to add
QMAKE_CXXFLAGS += -std=c++1zor anything I'd want. Unfortunately, this doesn't seem to be the case in the 5.9 kit.
I created a small testcase: https://github.com/KrzaQ/59test It compiles on mingw kits 5.6 through 5.8 (and I suppose it would compile on some of the older ones as well), but it fails on 5.9, because the following command is issued by make:
mingw32-make: Entering directory '[...]/build-59test-Desktop_Qt_5_9_0_MinGW_32bit-Debug' g++ -c -fno-keep-inline-dllexport -pipe -std=c++14 -g -std=gnu++11 -Wextra -Wall -W -fexceptions -mthreads -DUNICODE -DQT_DEPRECATED_WARNINGS -DQT_QML_DEBUG -DQT_CORE_LIB -I..\59test -I. -IC:\pro\Qt\5.9\mingw53_32\include -IC:\pro\Qt\5.9\mingw53_32\include\QtCore -Idebug -IC:\pro\Qt\5.9\mingw53_32\mkspecs\win32-g++ -o debug\main.o ..\59test\main.cpp
Specifically, this part:
-std=c++14 -g -std=gnu++11
I don't know why
-std=gnu++11is being added, overriding my wishes. I tried looking around for the mkspec, but I found nothing obvious to me.
Any help would be appreciated.
Eeli K last edited by
@krzaq I don't know if this helps, but gnu++xx is different than ++xx - gnu++xx adds gnu extensions. Have you tried
CONFIG -= gnu++11
krzaq last edited by krzaq
@Eeli-K I don't think this is directly connected (i.e.
CONFIG += c++14works on MSVC, which has different naming scheme entirely).
Nevertheless, I have just tried the following, but it didn't fix my problem:
CONFIG -= c++11 CONFIG -= c++14 CONFIG -= gnu++11 CONFIG -= gnu++14
You have to modify the mkspec to fit your need.
As for MSVC, there's no setting of any standard, the compiler always uses the latest that was implemented by Microsoft.
krzaq last edited by
@SGaist That's not an acceptable solution. Modifying the installation on every machine used to build/develop the project because there's a bug in the new Qt is ridiculous.
Btw: MSVC does, in fact, have a standard switch since the latest version (or maybe one back):
/std:latest. Without it you can't have i.e.