[Windows RT Development and Hacking] GoodDayToDie:
So, I've been at this for about 48 hours now (not continuously, but closer than you might think) and I figured I should take a break from modifying project files and puzzling over alignment issues to discuss the project, share some of the problems I've been having and ask if anybody can help, and so on.

The general idea is "Chromium build for Windows (on x86/x64) and build on ARM (for Linux), so there must be a way to build it for Windows on ARM". For the most part, that even looks like it's true. Probably at least 80% of 654 Visual Studio projects (no, that's not a joke) either build just fine with only minor amounts of work, or are things that we don't actually need (I'll try building the test suites... once everything else builds!!)

Areas that have given me problems (caution: some chance of brief rants ahead):

v8. Less than you might think, though. Setting the flags for Arm seems to have been enough.

Sandbox. There's a fair bit of thunking coded in assembly going on in the sandbox for x86. Not sure what's up with it (I don't know exactly how the Chromium sandbox works) but it'll have to come out or be replaced. The Linux (including ARM) sandbox seems to be SELinux-based, which doesn't help at all.

Native Client (NaCl). I think all the assembly is in test code, though, so I may just boldly #ifdef if all away.

libjpg-turbo (libjpg). Piles of carefully optimized assembly... for x86 and x64. There is a set of ARM assembly (for Linux) that Visual Studio won't compile, but something else might... or I may tweak until it works. Of course, I could also just accept the speed hit and use the version of libjpg implemented in nice, portable C.

Anything where the developers tried to use some SSE to speed things up. I may be able to replace it with NEON code, or I may just remove it and hope **** doesn't break. We'll see.

Inline assembly in general. Even when it's ARM assembly, Visual Studio / CL.exe don't want anything to do with it (__asm is apparently now an invalid keyword). I suspect I'll have to just pull the assembly out into stand-alone functions in their own files, then compile them to object files and link them back in later. If I can figure out the best way to do this (for example, I'll want to inline the asm functions) then it shouldn't impact performance. Seriously though, I kind of hate inline assembly. I can read assembly just fine, but I'm usually staring at it in a debugger or disassembly tool, not in the middle of source code I'm trying to build...

Everywhere that the current state of the CPU is cared about (exception and crash handlers, in particular) because the CONTEXT structure is, of course, CPU-specific. They're pretty easy to get past, though.

Low-level functions, like MemoryBarrier. Fortunately, it's implemented in ntdll.h... but as a macro, which breaks at least half the places it's referenced. Solution: where it breaks things, undefine the macro and just have it be an inline function that does what the macro did.

Running out of memory. Not even joking... well, OK, a little bit. I've got 32GB; I won't actually run out. Both Visual Studio and cl.exe do at times, though!. Task Manager says VS is currently using 1,928 MB, and before I restarted it, it broke 2.5GB private working set. Pretty good for a program that for some reason is still 32-bit...

Goddamn compiler flags. Seriously, every single project (I mentioned there are over 600, right?) has its LIBPATHs hardcoded to point at x86. Several projects have /D:_X86_ or similar (that's supposed to be set by the build tools, not the user, you idiots...) which plays merry hell with the #ifdef guards. Everything has /SAFESEH specified, not in the actual property table where the IDE could have removed it (unneeded and invlaid on ARM) but in the "extra stuff we'll pass on the build command line" field, which means every single .EXE/.DLL project must be modified or the linker will fail.

My current biggest goal is the JPG library; nobody wants to use a browser without it. After that, I'll tackle the sandbox, leaving NaCl for last... well, last before whatever else crops up.

Anyhow, thoughts/comments/advice are welcome... in the mean time, I'm going to go eat something (for the first time in ~22 hours) and then get some sleep.