Error during installation: ‘class QComboBox’ has no member named ‘setPlaceholderText’

[Griffin]

Hi everyone,

I'm following the instructions here to install Dolphin on Ubuntu, and I'm encountering this error on the final step when I run "sudo make install":

Code:

[ 83%] Building CXX object Source/Core/DolphinQt/CMakeFiles/dolphin-emu.dir/Debugger/MemoryWidget.cpp.o
/home/griffin/dolphin-emu/Source/Core/DolphinQt/Debugger/MemoryWidget.cpp: In member function ‘void MemoryWidget::CreateWidgets()’:
/home/griffin/dolphin-emu/Source/Core/DolphinQt/Debugger/MemoryWidget.cpp:108:21: error: ‘class QComboBox’ has no member named ‘setPlaceholderText’
 108 |   m_search_address->setPlaceholderText(tr("Search Address"));
     |                     ^~~~~~~~~~~~~~~~~~
make[2]: *** [Source/Core/DolphinQt/CMakeFiles/dolphin-emu.dir/build.make:1476: Source/Core/DolphinQt/CMakeFiles/dolphin-emu.dir/Debugger/MemoryWidget.cpp.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:2256: Source/Core/DolphinQt/CMakeFiles/dolphin-emu.dir/all] Error 2
make: *** [Makefile:156: all] Error 2

I found this thread where someone said this error results from using an older version of Qt, but from the output of the dependency install command, it looks like I'm already using version 5.15:

Code:

qtbase5-dev is already the newest version (5.15.3+dfsg-2ubuntu0.2).
qtbase5-private-dev is already the newest version (5.15.3+dfsg-2ubuntu0.2).

I also found that "qmake -v" shows a version 5.9.7 Anaconda install:

Code:

QMake version 3.1
Using Qt version 5.9.7 in /home/griffin/anaconda3/lib

I'm not sure whether this is relevant or how to determine which version is being used.

I'd greatly appreciate any help with resolving this issue. Thank you!

[MayImilae]

Dolphin currently uses Qt 6.3.0. What version of Dolphin are you trying to build?

[AdmiralCurtiss]

Some high version of Qt5 should also work. Qt 5.15 should work, so I'm guessing you have multiple Qt versions installed and CMake happens to pick the wrong one.

[GenerationI]

Strange. I'm on Linux Mint 21 (based on Ubuntu) and I get this:

~$ qmake -v
QMake version 3.1
Using Qt version 5.15.3 in /usr/lib/x86_64-linux-gnu

I tried rebuilding and installing from scratch the current version of Dolphin just now and it worked. I don't know if this is relevant but I always pull the git submodules recursively with the the following command:

git submodule update --init --recursive

My only other guess atm is that it depends on which compiler you use, because some header files are sensitive to that.