On Tuesday 15 July 2014 08:15:55 Thiago Macieira wrote: > On Tuesday 15 July 2014 15:32:10 Milian Wolff wrote: > > It seems to be related to the number of jobs running, a "make -j1" seems > > to > > work most of the time, yet a "make -j40" on a compile cluster fails most > > of > > the time. > > Theories: > 1) one of the compilation processes started before the PCH-creation finished > a) because qmake generated the wrong rules; > b) because you have a bug in make > 2) the rules are right, but the PCH creation is failing due to bug in the > toolchain
OK, but why are PCH's enabled by default? The output of configure --help does not indicate that. I.e. why is -include .pch/Qt5Something even passed to GCC in the first place by default? > Please check all three possibilities. The easiest is to check the rules. Let > me take the example of QtCore and qglobal.o: > > .obj/qglobal.o: > /home/thiago/src/qt/qt5/qtbase/src/corelib/global/qglobal.cpp > ../../include/QtCore/qstring.h \ > [...] > .pch/Qt5Core.gch/c++ > $(CXX) -c -include .pch/Qt5Core $(CXXFLAGS) $(INCPATH) -o > .obj/qglobal.o /home/thiago/src/qt/qt5/qtbase/src/corelib/global/qglobal.cpp > > So there *is* a rule that makes qglobal.o depend on the PCH output for me. > It doesn't look like a qmake bug to me. > > To check if the bug is in make, you have to watch your system. When it > enters a new build, does it halt for a second or two trying to precompile > the headers, and *then* launch the other 40 processes? If so, it's not a > make bug. > > If the above two prove correct, by process elimination we arrive at a bug in > the toolchain. You maintioned that this happens when you're using Icecream, > only sometimes, and when using a high -j. I have two theories for this: > > 1) creation got submitted to another machine and the transfer of the file > back failed > 2) creation succeeded, but icecc did not submit the PCH file to the remote > machine to compile. > > In fact, #2 and remote building is usually at odds. Teambuilder had never > fixed that. The scripts had rules to remove the PCH including so remote > building would work. That does sound like a valid assumption on why it all fails on my end. I'll just stick to configure with -no-pch. Thanks -- Milian Wolff m...@milianw.de http://milianw.de _______________________________________________ Development mailing list Development@qt-project.org http://lists.qt-project.org/mailman/listinfo/development
