Solved QT 5.12 make Mingw 32 release

[AmrCoder]

Hello,

Iam using QT 5.12 the last version of QT and after i installed it I found that the MinGW that comes with QT is 64 bit and no 32 version as in the old versions it always 32 bit and I was always releasing the applications in 32 so it can work on both.

Now most of the third party libraries I compiled it in old versions of Mingw32 and it can't work on Mingw64 it gives me undefine reference in most cases.

when I search about Mingw I found that the 64 should also work on 32 iam not sure, so is there any way to make a Mingw 32 release in the QT 5.12?
iam using Windows 10

Thanks in advance.

[mrjj]

Hi
5.11.3 seems to be the last to include 32 bit mingw.

You can compile a 32 bit version of 5.12 if you really need 5.12 32 bit.

[AmrCoder]

Yes i know but is there a way to make a 32 release from the 64 there is something like this here
they add the -m32 to the compiler and it makes a 32 release and then tests by checking the

sizeof(size_t)

if it's 4 for 32 or 8 for 64, I already test by adding this to the argument in QT but it did not work

[mrjj]

@AmrCoder
well the Qt DLL files are still 64bit and a 32 bit app wont load them.
But yes, its the same thing as link show.
You just have to compile ALL of Qt to get same effect :)

I think using 5.11.3 might be faster than compiling a new Qt but
if you already have all dependencies and a powerfull pc, its
not the biggest task.

[AmrCoder]

the last question please, is there any chance for 32 version in the next versions QT 5.12.1 for example or it will be only 64?

[mrjj]

@AmrCoder
Most likely only 64 bit.

[nayk]

I build Qt 5.12 with MinGW 7.3.0 32bit from source. Download: link

[AmrCoder]

I download it and add it to my QT 5.12 and it worked perfectly, really I appreciated that many thanks for you <3 and i hope they make a 32 bit release in the next versions if there is a way we can make a suggestion because most of us need our apps to be in 32 bit release, Thanks again @nayk

[nayk]

you are welcome

[max.chen]

Hi nayk,

I download it and add it to my QT 5.12 , but When i run the app i get some error about this:

qt.qpa.plugin: Could not find the Qt platform plugin "windows" in ""

Where have I not set up?

[AmrCoder]

I solve it by copying the folder of the 5.12.0\mingw73_32\plugins\platforms to the same folder that has the exe programe if there is a solution to solve it without this it will be better

[nayk]

@max.chen try copying the "platforms/qwindows.dll" file to the application subdirectory "platforms".
qwindows.dll - for release mode, qwindowsd.dll - for debug mode.
Other plugins libraries may also be needed for you application.

[nayk]

I compiled this version with OpenSSL 1.1.1a and put the necessary dll in the "_dll_for_app" directory (libcrypto-1_1.dll, libssl-1_1.dll). OpenSSL is used by Qt5Network for https connections.
MySql 5.6 - for MySQL Qt plugin
PosgreSQL 9.6.11 - for PostgreSQL Qt plugin

[aha_1980]

@AmrCoder said in QT 5.12 make Mingw 32 release:

I download it and add it to my QT 5.12 and it worked perfectly, really I appreciated that many thanks for you <3 and i hope they make a 32 bit release in the next versions if there is a way we can make a suggestion because most of us need our apps to be in 32 bit release,

You should write a mail to the Interest mailing list or directly create a suggestion in Jira.

In either case, please provide a link here, so we can follow the discussion. Thanks!

Edit: Follow-up: https://lists.qt-project.org/pipermail/interest/2018-December/031798.html

[Longxr]

@AmrCoder Add this environment variable

[KATO2]

the solution proposed by @nayk works very well, however this is a partial solution, because each time you want to update Qt, you need to build a new version of Qt for x32. I think there is a way to cross compile your application using mingw-64w, but i don't know how to do that. Maybe someone can instruct us how to do it!

[jsulm]

@KATO2 Why do you want to cross compile? Just use MinGW32 to build Qt.

[sierdzio]

FYI: Qt 5.12.2 will ship with Mingw 32 packages included. UWP packages will be dropped.

[KATO2]

@jsulm official QT 5.12.0 and QT 5.12.1 includes only MinGW 64, not MinGW 32 version was included.

[aha_1980]

@KATO2 Correct. Nevertheless, that's compiling Qt from source, not cross-compiling.