[Linux] gcc-11 Build failures Meta-Issue

[Shoegzer]

RPCS3 is now failing to build on Linux plaforms.

Test system / background:

• OS: Linux Mint 20.1 / kernel 5.11
• Compiler: gcc-11.1.0
• Problem build: f103004
• Last good build: 309759b
• Build log: here

[Nekotekina]

You need to patch Qt headers a little in order to build on gcc-11.

[MSuih]

Qt headers issue is tracked in #10291.

[Shoegzer]

Thanks both of you. Following #10291 I patched qtconcurrentthreadengine.h as:

sed -i 's/ThreadEngineStarter<void>(ThreadEngine<void> \*_threadEngine)/ThreadEngineStarter(ThreadEngine<void> \*_threadEngine)/' /opt/qt515/include/QtConcurrent/qtconcurrentthreadengine.h

This worked, and rpcs3 compiles successfully with the change.

Is there a workaround planned for rpcs3 before I close this out, or will the above patch be required until gcc itself is fixed? Was surprised to see rpcs3 jump to gcc-11 since it's so new, perhaps that was premature or is it needed for some reason?

[kd-11]

gcc-10 has far more errors with newer submodule updates than gcc-11. If you try with gcc-10 it fails long before reaching that qt header.

[p01arst0rm]

@Shoegzer @kd-11 the gcc error in Qt is currently suggested to be a compiler bug. more info/ a fix is available here:

https://bugreports.qt.io/browse/QTBUG-91909

[MSuih]

Reports done on the Qt side are useless as only paying customers will get updates to 5.15, and we're not going to be updating to 6.1 soon. If it really is a compiler bug then it should be reported to GCC so that they can fix it.

Are there any other issues remaining for gcc-11?

[p01arst0rm]

Reports done on the Qt side are useless as only paying customers will get updates to 5.15, and we're not going to be updating to 6.1 soon. If it really is a compiler bug then it should be reported to GCC so that they can fix it.

Are there any other issues remaining for gcc-11?

its a one-line change to a single file, i wanted to highlight you can make the change personally as a hotfix :)

i just compiled with gcc-11 from the arch testing branch on 5.10; except this Qt problem, there were no other issues.

[MSuih]

Closing as reported issues have been resolved. There was some talk of earlier gcc-11 versions having some other issue that was fixed, so make sure your tools up-to-date. If some other problems still remain, ask for this to be reopened or open a new issue.