[Buildroot] [PATCH v6 0/3] Qt WebEngine support

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Hello,

On Fri, 11 Aug 2017 21:29:37 +0200, Bj?rn Kirchner wrote:
> Hello Ga?l,
> 
> Am Thu, 10 Aug 2017 21:33:55 -0400
> schrieb Ga?l PORTAY <gael.portay@savoirfairelinux.com>:
> 
> > Hi all,
> > 
> > The purpose of this patch series is to continue the integration of
> > Qt5 WebEngine in buildroot; started long time ago by Akihiko Odaki
> > [1] and Julien Corjon [2].
> >   
> ...
> > 
> > I have tested it with a rpi 3; and I will be glad if someone else has
> > another EGL platform to test it.
> >   
> 
> Thanks for your efforts. I have tried to compile the qt5webengine
> package for Qt 5.9.1. Unfortunatly there is a build error.
> 
> I applied your patches to buildroot git master. My build machine is
> Debian 8 64bit, my target is ARM Cortex-A8 (Olimex A10 Lime board
> with Allwinner A10 CPU).
> 
> It looks like the build is calling the system compiler of the host,
> which eventually seems to lead to a missing include file
> (bits/c++config.h). Please see snipped from build output:
> 
> --- snip from build output ---
> 
> [8/9559] CXX v8_snapshot/obj/v8/mkpeephole/bytecode-operands.o
> FAILED: v8_snapshot/obj/v8/mkpeephole/bytecode-operands.o 
> /usr/bin/g++ -MMD -MF
> v8_snapshot/obj/v8/mkpeephole/bytecode-operands.o.d
> -DV8_DEPRECATION_WARNINGS -DUSE_UDEV -DUSE_AURA=1 -DUSE_OPENSSL_CERTS=1
> -DUSE_OZONE=1 -DNO_TCMALLOC -DDISABLE_NACL -DENABLE_TASK_MANAGER=1
> -DENABLE_THEMES=1 -DFULL_SAFE_BROWSING -DSAFE_BROWSING_CSD
> -DSAFE_BROWSING_DB_LOCAL -DCHROMIUM_BUILD -DFIELDTRIAL_TESTING_ENABLED
> -DTOOLKIT_QT -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE
> -D_LARGEFILE64_SOURCE -DNDEBUG -DNVALGRIND
> -DDYNAMIC_ANNOTATIONS_ENABLED=0 -DV8_I18N_SUPPORT -DV8_TARGET_ARCH_ARM
> -DCAN_USE_ARMV7_INSTRUCTIONS -DCAN_USE_VFP3_INSTRUCTIONS
> -DUSE_EABI_HARDFLOAT=1 -Iv8_snapshot/gen -I../../3rdparty/chromium
> -I../../3rdparty/chromium/v8/include -Iv8_snapshot/gen/v8/include
> -I../../3rdparty/chromium/v8 -fno-strict-aliasing
> --param=ssp-buffer-size=4 -fstack-protector -funwind-tables -fPIC -pipe
> -pthread -m32 -msse2 -mfpmath=sse -mmmx -g0 -fvisibility=hidden

There is -m32, so it's trying to build a 32 bit binary on your x86_64
machine...

> -Wno-unused-local-typedefs -Wno-maybe-uninitialized
> -Wno-missing-field-initializers -Wno-unused-parameter -O3 -fno-ident
> -fdata-sections -ffunction-sections -fno-threadsafe-statics
> -fvisibility-inlines-hidden -std=gnu++11 -fno-rtti -fno-exceptions
> -Wno-deprecated -Wno-narrowing
> -c ../../3rdparty/chromium/v8/src/interpreter/bytecode-operands.cc -o
> v8_snapshot/obj/v8/mkpeephole/bytecode-operands.o In file included
> from /usr/include/c++/4.9/ios:38:0,
> from /usr/include/c++/4.9/ostream:38,
> from ../../3rdparty/chromium/v8/src/globals.h:11,
> from ../../3rdparty/chromium/v8/src/interpreter/bytecode-operands.h:8,
> from ../../3rdparty/chromium/v8/src/interpreter/bytecode-operands.cc:5: /usr/include/c++/4.9/iosfwd:38:28:
> fatal error: bits/c++config.h: No such file or directory #include
> <bits/c++config.h> ^ compilation terminated.

... but you don't have the 32 bit development headers installed.

Questions are:

 * Is it normal that qtwebengine builds this for the host machine. It
   could be normal, if it's a program later used to generate data/code ?

 * If it's normal that it's built for the host, why do they force
   building for 32 bits by passing -m32 ?

Best regards,

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com