Hello, On Thu, 6 Feb 2020 17:43:53 +0300 Dmitry Shachnev wrote:
> On Thu, Feb 06, 2020 at 11:08:41AM -0300, Lisandro Damián Nicanor Pérez Meyer wrote: > > Lars pointed out [1] that QtQml (and so I guess this lib, will need to double > > check) would really benefit from a i386 build with SSE2 enabled. > > > > [1] > > Already discussed on IRC, but for the record: > > Actually Qt QML has a runtime requirement for SSE2, so I am not sure the > non-SSE2 build makes sense: > > https://sources.debian.org/src/qtdeclarative-opensource-src/5.12.5-5/src/qml/qml/v8/qv8engine.cpp/#L143 > > I think we should just switch the default build to SSE2 by passing > CONFIG+=sse2 to qmake when DEB_HOST_ARCH_CPU = i386. I doubt it. First, the line you reference (and any other reference to SSE2) is missing from the current sources, second, it is alleged qml should work without sse2 just with interpreted bytecode. However, I tried the dual build and it is actually hard to compile it with sse2 enabled: CONFIG+=sse2 QMAKE_CxxxFLAGS+=-msse2 etc. all don't work. Either it does nothing, or it fails to enable the jit in build. It seems this feature is hard coded in the file /usr/lib/i386-linux-gnu/qt5/mkspecs/qmodule.pri By editing that file I found out I needed to change QT.global_private.enabled_features to make it work. Which is super ugly. You can see the result here: https://salsa.debian.org/jpalecek-guest/qtdeclarative I still need to test the resulting binaries. Regards Jiri Palecek
