Details
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Bug
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Resolution: Unresolved
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P3: Somewhat important
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None
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5.15.3
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None
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macOS
Description
The following program successfully compiles
// qt_osg_bug.cpp #include <QOpenGLContext> #include <osg/Node>
while this one fails (include order changed)
// qt_osg_bug.cpp #include <osg/Node> #include <QOpenGLContext>
with the error
clang++ -I/opt/local/include -iframework /opt/local/libexec/qt5/lib -isystem /opt/local/libexec/qt5/lib/QtGui.framework/Headers -isystem /Library/Developer/CommandLineTools/SDKs/MacOSX12.3.sdk/System/Library/Frameworks/OpenGL.framework/Headers -isystem /opt/local/libexec/qt5/lib/QtOpenGL.framework/Headers -Wno-deprecated-declarations -std=c++14 -o qt_osg_bug.cpp.o -c qt_osg_bug.cpp In file included from qt_osg_bug.cpp:2: In file included from /opt/local/libexec/qt5/lib/QtGui.framework/Headers/QOpenGLContext:1: In file included from /opt/local/libexec/qt5/lib/QtGui.framework/Headers/qopenglcontext.h:61: /opt/local/libexec/qt5/lib/QtGui.framework/Headers/qopenglversionfunctions.h:1096:23: error: unknown type name 'GLDEBUGPROC' QT_OPENGL_DECLARE(QT_OPENGL_4_3_FUNCTIONS); ^ 1 error generated.
Both are compiled as follows:
clang++ -I/opt/local/include -iframework /opt/local/libexec/qt5/lib -isystem /opt/local/libexec/qt5/lib/QtGui.framework/Headers -isystem /Library/Developer/CommandLineTools/SDKs/MacOSX12.3.sdk/System/Library/Frameworks/OpenGL.framework/Headers -isystem /opt/local/libexec/qt5/lib/QtOpenGL.framework/Headers -Wno-deprecated-declarations -std=c++14 -o qt_osg_bug.cpp.o -c qt_osg_bug.cpp
The issue boils down to the inclusion order of these two files
// qt_osg_bug.cpp #include <qopengl.h> // reachable from <QOpenGLContext> #include <osg/GLDefines> // reachable from <osg/Node>
<qopegl.h:279> protects the declaration of GLDEBUGPROC with a define guard
// qopegl.h:279 #ifndef GL_KHR_debug typedef void (APIENTRY *GLDEBUGPROC)(GLenum source,GLenum type,GLuint id,GLenum severity,GLsizei length,const GLchar *message,const GLvoid *userParam); #endif
However, this macro is also defined by <osg/GLDefines> (here). So if <osg/GLDefines> is included before <qopengl.h> the function pointer GLDEBUGPROC is left undefined which leads to an error when it latter referenced in <qopenglversionfunctions.h>.
I am not sure if OpenSceneGraph is at fault here and if GLDEBUGPROC prototype should be defined when GL_KHR_debug is defined.
Guessing from code found in <qopenglextrafunctions.h:55> there have been attempts to fix similar issues for other systems. If this is not the right place please feel free to close this and hopefully point us to the right tracker.
Note: while this report is for arm64 macOS 12.4, the issue is observed in macOS 10 on x86_64 as well.