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Bug
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Resolution: Invalid
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P3: Somewhat important
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None
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5.6.2
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None
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macOS
Summary:
Qt app took longer time to execute QOpenGLFunctions_2_0::initializeOpenGLFunctions if it was built on Mac 10.10. No matter which platform it ran.
Desc:
To reproduce this issue, I built the Qt OpenGL example on both Mac 10.10 and Mac 10.11. And print elapsed time of QOpenGLFunctions_2_0::initializeOpenGLFunctions().
if (needsInitialize) {
QElapsedTimer timer;
timer.start();
initializeOpenGLFunctions();
qDebug() << "initializeOpenGLFunctions lasted for " << timer.elapsed();
initialize();
}
The outputs were:
// built on Mac 10.10 initializeOpenGLFunctions lasted for 137 // build on Mac 10.11 initializeOpenGLFunctions lasted for 2
The build environments were:
Qt 5.6.2 MacOS 10.11.6 Apple LLVM version 7.3.0 (clang-703.0.31) Target: x86_64-apple-darwin15.6.0 Thread model: posix Mac 10.10. Apple LLVM version 6.1.0 (clang-602.0.53) (based on LLVM 3.6.0svn) Target: x86_64-apple-darwin14.5.0 Thread model: posix
To make sure it's a Qt issue, I also built it on Mac 10.10 with Qt 5.9.1 and the issue did not appear.
// Output, Mac 10.10 with Qt 5.9.1 initializeOpenGLFunctions lasted for 0