Can't compile on raspberry pi

[TheCoder3156]

It fails to compile on a raspberry pi 3. Here is the error.

[ 76%] Building CXX object qt/CMakeFiles/mgba-qt.dir/DisplayGL.cpp.o
In file included from /usr/include/GL/gl.h:2055,
                 from /home/pi/mgba-0.6.3/src/platform/opengl/gl.h:21,
                 from /home/pi/mgba-0.6.3/src/platform/qt/DisplayGL.cpp:17:
/usr/include/GL/glext.h:468:19: error: conflicting declaration ‘typedef ptrdiff_t GLsizeiptr’
 typedef ptrdiff_t GLsizeiptr;
                   ^~~~~~~~~~
In file included from /usr/include/arm-linux-gnueabihf/qt5/QtGui/qopengl.h:99,
                 from /usr/include/arm-linux-gnueabihf/qt5/QtOpenGL/qgl.h:45,
                 from /usr/include/arm-linux-gnueabihf/qt5/QtOpenGL/QGLWidget:1,
                 from /home/pi/mgba-0.6.3/src/platform/qt/DisplayGL.h:21,
                 from /home/pi/mgba-0.6.3/src/platform/qt/DisplayGL.cpp:6:
/usr/include/GLES3/gl31.h:73:25: note: previous declaration as ‘typedef khronos_ssize_t GLsizeiptr’
 typedef khronos_ssize_t GLsizeiptr;
                         ^~~~~~~~~~
In file included from /usr/include/GL/gl.h:2055,
                 from /home/pi/mgba-0.6.3/src/platform/opengl/gl.h:21,
                 from /home/pi/mgba-0.6.3/src/platform/qt/DisplayGL.cpp:17:
/usr/include/GL/glext.h:469:19: error: conflicting declaration ‘typedef ptrdiff_t GLintptr’
 typedef ptrdiff_t GLintptr;
                   ^~~~~~~~
In file included from /usr/include/arm-linux-gnueabihf/qt5/QtGui/qopengl.h:99,
                 from /usr/include/arm-linux-gnueabihf/qt5/QtOpenGL/qgl.h:45,
                 from /usr/include/arm-linux-gnueabihf/qt5/QtOpenGL/QGLWidget:1,
                 from /home/pi/mgba-0.6.3/src/platform/qt/DisplayGL.h:21,
                 from /home/pi/mgba-0.6.3/src/platform/qt/DisplayGL.cpp:6:
/usr/include/GLES3/gl31.h:74:26: note: previous declaration as ‘typedef khronos_intptr_t GLintptr’
 typedef khronos_intptr_t GLintptr;
                          ^~~~~~~~
qt/CMakeFiles/mgba-qt.dir/build.make:270: recipe for target 'qt/CMakeFiles/mgba-qt.dir/DisplayGL.cpp.o' failed
make[2]: *** [qt/CMakeFiles/mgba-qt.dir/DisplayGL.cpp.o] Error 1
CMakeFiles/Makefile2:216: recipe for target 'qt/CMakeFiles/mgba-qt.dir/all' failed
make[1]: *** [qt/CMakeFiles/mgba-qt.dir/all] Error 2
Makefile:151: recipe for target 'all' failed
make: *** [all] Error 2

[Raijinili]

It looks like you have two versions of GL installed, and both are being included.

What if you turn off BUILD_QT in CMake? Or is QT required on the Pi?

[TheCoder3156]

I would prefer the qt if possible. Any idea on how to fix the conflict?

[Raijinili]

May be a duplicate of #218.

In that issue, the workaround was,

Try installing libepoxy-dev and seeing if that affects anything.

[endrift]

It's definitely the same issue. However, that one was closed with a workaround instead of a resolution.

[endrift]

Please let me know if this patch fixes it

diff --git a/src/platform/opengl/gl.h b/src/platform/opengl/gl.h
index a6412e919..a37f7736e 100644
--- a/src/platform/opengl/gl.h
+++ b/src/platform/opengl/gl.h
@@ -18,8 +18,10 @@ CXX_GUARD_START
 #ifdef _MSC_VER
 #include <windows.h>
 #endif
+#ifndef GL_GLES_PROTOTYPES
 #include <GL/gl.h>
 #endif
+#endif
 
 #include "platform/video-backend.h"
 
diff --git a/src/platform/qt/DisplayGL.cpp b/src/platform/qt/DisplayGL.cpp
index 28b191831..7de3d17d3 100644
--- a/src/platform/qt/DisplayGL.cpp
+++ b/src/platform/qt/DisplayGL.cpp
@@ -15,15 +15,15 @@
 
 #include <mgba/core/core.h>
 #include <mgba-util/math.h>
-#ifdef BUILD_GL
-#include "platform/opengl/gl.h"
-#endif
 #if !defined(_WIN32) || defined(USE_EPOXY)
 #include "platform/opengl/gles2.h"
 #ifdef _WIN32
 #include <epoxy/wgl.h>
 #endif
 #endif
+#ifdef BUILD_GL
+#include "platform/opengl/gl.h"
+#endif
 
 using namespace QGBA;
 

[TheCoder3156]

Forgot about this. Sorry. I can't help because I did a installed a different is on the pi

[vaguerant]

@endrift

Please let me know if this patch fixes it

Three years later, I'm trying to build on a Raspberry Pi 3 and encountering the same issue. This patch (applied manually as things have moved around slightly since 3 years ago) didn't help at all. I did a make clean and attempted another build but the result was exactly the same error as before.

EDIT: I also tried installing libepoxy-dev, the workaround suggested in the previous issue on this subject, but that doesn't seem to have made any difference on my end either. make clean; make; same error.

[endrift]

I'll see if I can find an RPi to test on.

[Dimensional]

I attempted to compile this on my Rpi4, on 32-bit Raspberry Pi OS. Things I ran into were:

1. There was no QT5LinguistTools, which didn't interfere with compiling.
2. When compiling mgba-qt, I would get an error at the final phase, where linking would error, stating /usr/bin/ld: CMakeFiles/mgba-qt.dir/library/LibraryController.cpp.o: undefined reference to symbol '__atomic_compare_exchange_8@@LIBATOMIC_1.0' /usr/bin/ld: //lib/arm-linux-gnueabihf/libatomic.so.1: error adding symbols: DSO missing from command line

• Manually adding the file, with full path, to the qt/CMakeFiles/mgba-qt.dir/link.txt document fixes that error

3. After successfully compiling this, the final thing I've run across is that the emulator gives a message stating Failed to create an appropriate display device, falling back to software display. Games may run slowly, especially with larger windows

• I haven't been able to figure out how to correct this, and the only thought could be needing to add in compiler flags to use overlay hacks, or one of the libraries from /opt/vc/lib.

[retropieuser]

I attempted to compile this on my Rpi4, on 32-bit Raspberry Pi OS. Things I ran into were:

1. There was no QT5LinguistTools, which didn't interfere with compiling.

2. When compiling mgba-qt, I would get an error at the final phase, where linking would error, stating
   `/usr/bin/ld: CMakeFiles/mgba-qt.dir/library/LibraryController.cpp.o: undefined reference to symbol '__atomic_compare_exchange_8@@LIBATOMIC_1.0'`
   `/usr/bin/ld: //lib/arm-linux-gnueabihf/libatomic.so.1: error adding symbols: DSO missing from command line`


* Manually adding the file, with full path, to the qt/CMakeFiles/mgba-qt.dir/link.txt document fixes that error


1. After successfully compiling this, the final thing I've run across is that the emulator gives a message stating
   `Failed to create an appropriate display device, falling back to software display. Games may run slowly, especially with larger windows`


* I haven't been able to figure out how to correct this, and the only thought could be needing to add in compiler flags to use overlay hacks, or one of the libraries from /opt/vc/lib.

So I found if you start the emulator from command line and add -l 0 you get rid of the error message at the start. So now I've got it functioning on Retropie which is quite fun to mess around with

[Dimensional]

I attempted to compile this on my Rpi4, on 32-bit Raspberry Pi OS. Things I ran into were:

1. There was no QT5LinguistTools, which didn't interfere with compiling.

2. When compiling mgba-qt, I would get an error at the final phase, where linking would error, stating
   `/usr/bin/ld: CMakeFiles/mgba-qt.dir/library/LibraryController.cpp.o: undefined reference to symbol '__atomic_compare_exchange_8@@LIBATOMIC_1.0'`
   `/usr/bin/ld: //lib/arm-linux-gnueabihf/libatomic.so.1: error adding symbols: DSO missing from command line`


* Manually adding the file, with full path, to the qt/CMakeFiles/mgba-qt.dir/link.txt document fixes that error


1. After successfully compiling this, the final thing I've run across is that the emulator gives a message stating
   `Failed to create an appropriate display device, falling back to software display. Games may run slowly, especially with larger windows`


* I haven't been able to figure out how to correct this, and the only thought could be needing to add in compiler flags to use overlay hacks, or one of the libraries from /opt/vc/lib.

So I found if you start the emulator from command line and add -l 0 you get rid of the error message at the start. So now I've got it functioning on Retropie which is quite fun to mess around with

-l 0 disables log level mask. It doesn't change how the emulator loads to circumvent the error.

[Lokathor]

I can confirm that the atomic issue is still present on the 32-bit Raspberry Pi OS:

lokathor@eva00:~/mgba/build $ make
[ 10%] Built target updater-stub
[ 10%] Built target mgba-version-info
[ 59%] Built target mgba
[ 61%] Built target mgba-sdl
[ 62%] Built target discord-rpc
[ 62%] Automatic MOC for target mgba-qt
[ 62%] Built target mgba-qt_autogen
[ 62%] Linking CXX executable mgba-qt
/usr/bin/ld: CMakeFiles/mgba-qt.dir/library/LibraryController.cpp.o: undefined reference to symbol '__atomic_compare_exchange_8@@LIBATOMIC_1.0'
/usr/bin/ld: /lib/arm-linux-gnueabihf/libatomic.so.1: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
make[2]: *** [qt/CMakeFiles/mgba-qt.dir/build.make:1690: qt/mgba-qt] Error 1
make[1]: *** [CMakeFiles/Makefile2:526: qt/CMakeFiles/mgba-qt.dir/all] Error 2
make: *** [Makefile:171: all] Error 2

However, the 64-bit version of the Raspberry Pi OS does successfully build and run mGBA-qt

[foxhound311]

@Lokathor i got it built on 32bit bullseye. i used these flags:

cmake -DCMAKE_BUILD_TYPE=RELEASE -DCMAKE_CXX_FLAGS="-march=armv8-a -mtune=cortex-a72" ..

and its up and running. change the renderer to GL. works fine

[Lokathor]

I can confirm that a default build doesn't work, but using those extra flags it does work.

Possibly the readme should be updated?