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Author: hfreyther

What is the size of a QList::Data, RenderObject?

What is the size of a QList::Data, RenderObject?

We tend to write classes without really caring about what the compile will do to create the binary file. When looking into performance and specially memory usage and you create certain objects thousands of times it becomes interesting of how much memory one is wasting for padding/no good reason. The Linux kernel hackers wrote a tool called pahole that will analyze the DWARF2 symbols and then spit out friendly messages like the one below. struct Data { class QBasicAtomicInt ref;…

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Memory profiling on GNU systems

Memory profiling on GNU systems

This is a small guide on how to observe memory allocations of a process. When carrying out a change it is not only of interest if all test cases still pass, if the benchmarks are faster but it is also important to figure out if there was a change in storage (stack and RAM) requirement. If you are using the GNU libc it is likely you have a /lib/libmemusage.so installed on your system. This library can be preloaded using LD_PRELOAD…

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Standing on the shoulders of giants – Fixing OpenOCD for the Beagleboard

Standing on the shoulders of giants – Fixing OpenOCD for the Beagleboard

Ever since fixing a little bug in the breakpoint code for the s3c2442 I’m subscribed to the OpenOCD mailinglist. One mail catched my eye, the mail was from a former Openmoko colleague Matt Hsu. He is working with most of the Taiwan Openmoko Team at the newly founded 0xlab and he was trying OpenOCD on the OMAP3 beagleboard. Yesterday I decided to go to their lab to hack with Matt on the Cortex-A8 support in OpenOCD. After downloading the datasheets,…

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People should have stayed with Typewriters… or why DHL sucks

People should have stayed with Typewriters… or why DHL sucks

Todays epic fail of DHL. When shipping a package you will have to leave a phone number to DHL. My dear reader, don’t worry, this phone number will never be used to call the receiver of the package in case of an error. So today I was checking the website where the package is and I’m supposed to call the DHL customer service. And in all glory of the internet and HTML they are not able to embed a link…

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Embedded syntax highlighted sourcecode into OpenOffice.org Write

Embedded syntax highlighted sourcecode into OpenOffice.org Write

The other day I was in need to embed some sourcecode into an OpenOffice.org Document. Normally I’m using LaTex and then can use the lgrind tool to prepare my sourcecode and use lgrindfile{file} to embed it. Well but I’m somehow required to use OpenOffice.org Writer to generate a MS Office .doc file. After some googling the GNU Source-highlight project came to rescue. I can syntax highlight my source code and patches, then I can use a HTML renderer to render…

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WebKit on non mainstream platforms

WebKit on non mainstream platforms

We have seen some interest in MIPS on the mailinglist and little in the bugtracker but no contribution from these folks. So the other week I decided to attempt to run some of our regression tests on a MIPS platform. The only problem is that I don’t have any MIPS hardware… can you change that? I had this idea of implementing enough of MacroAssembler to run/compile yarr with the RegexJIT.cpp. In the absence of MIPS hardware I used qemu-mipsel useremulation,…

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Searching for hardware donations

Searching for hardware donations

In the last couple of weeks I have increased my involvement with OpenEmbedded again. I have worked on ARM/x86, keeping uclibc building, getting more things build with uclibc, worked on Qt, started merging patches, specially the MIPS side of things have catched my eye. So everything is fine… if there wouldn’t be a little twist. I don’t have any ARM or MIPSEL targets at home. For my work on Openembedded and WebKit I’m searching for one MIPS and one ARM…

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OpenEmbedded gains ability to create Qt Embedded Linux SDK

OpenEmbedded gains ability to create Qt Embedded Linux SDK

Generating a Qt Embedded Linux SDK is as easy as typing bitbake meta-toolchain-qte. The generated SDK will contains the cross compiler, depedencies needed to recompile Qt Embedded Linux and Qt Emebedded Linux itself. Building Qt applications for the software is as easy as sourcing a script and invoking qmake2. More documentation can be found in a new section of the OpenEmbedded User manaul. Using SDKs produced by OpenEmbedded can greatly improve the productivity of development teams as they can start…

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Fun on the tech-bsd mailinglist

Fun on the tech-bsd mailinglist

For various reasons I’m subscribed to the tech bsd mailinglist and this mail made me smile. Let me quote some parts of it. “I don’t know who you are, but you do nothing. What do you do?I don’t see your name on any the source code.The source code does define the behaviour. Exactly. Perhaps thesource code is wrong, but it *EXACTLY DEFINES THE BEHAVIOUR*.So you shut up, loser. Just go away.” Theo de Raadt

Tale of a day/morning

Tale of a day/morning

My debug build of libQtWebKit finished and I thought the horror of linking a huge library is over and that I could start to debug. Turned out that gdb was segfaulting when launching my application. Eeeek., google… well googling for gdb and crash is not really finding gdb things. Okay so I was using cvs to get the latest version of gdb, compiling… *crash*. It seemed to crash in demangling, so just in case I was updating binutils and rebuilding…

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