Mono has a LLVM compiler. Is there anyway to use it with Emscripten (compile C# code to JavaScript)?
There is currently no out of the box way to do this. It might be possible, but it would require a lot of work. You would need to run mono in full AOT (ahead of time) compilation mode with the LLVM codegen. But there are many issues:
LLVM is currently not used for all methods, and mono falls back to it's own code generator in a number of cases. You would either need to get the LLVM suport working for all cases, or provide the JS code needed when LLVM cannot be used.
Mono currently has a number of architecture specific files (x86, amd64, arm, etc) and would probably need equivalent for JS, both for the code generation and for the AOT runtime.
And so on...
you can try to use C# Native
have a look here http://csnative.codeplex.com
Even if you run mono in full AOT and compile your program with LLVM it is not possible to use it with emscripten. This is quote from my discussion in mono group:
Besides that, no, it's not possible to use emscripten with mono's llvm output for a lot of reasons.
The output embeds calls to the mono runtime and some trampilines.
Mono use a custom LLVM with custom IR operations and that won't work on emscripten without some work on their end.
Related
I have a npapi plugin(bundle) for chrome, which use C++ and objective-c. now it needs to be build by google native client.
I wonder that can nacl support objective-c? how to compile o-c file by MakeFile
And if possible, how to build nacl plugin in Xcode? I tried, but i found that the libraries of nacl are " archive with no architecture specification".(use lipo -info *.a)
I hope someone to help me, thanks a lot!!!
If you use Objective-C without any of its usual libraries then you should be able to use the PNaCl toolchain (which is based on LLVM) to have it parse Objective-C. I'm not aware of projects that have done this, so you should definitely let folks on the mailing list know if you get something working (do keep the questions on SO, though!).
It sounds like your application won't be running on the open web (where only architecture-independent PNaCl can run, not NaCl), so you could either use the PNaCl toolchain to create a .pexe, or you could use the same toolchain to create a .nexe for each architecture you target. The documentation I linked to helps with both approaches, but note that using the PNaCl toolchain to create a .nexe is currently being improved. You can therefore follow the instructions on the bug tracker, or try out nacl-clang when it's released (or build it yourself if you're brave).
Mono can be compiled to native AOT executable using mkbundle.
My question is, how is the garbage collection works? If I compile Mono into AOT executable, should I make modification in the codes, to release unused variables / objects ?
Roughly speaking, after AOT compilation your application no longer needs JIT at runtime, but you still get GC and almost everything CLR offers except some part of reflection (Emit related).
Limitations are documented in http://www.mono-project.com/AOT
You don't need to modify your code generally except you need to remove anything that AOT does not support.
References:
http://tirania.org/blog/archive/2006/Aug-17.html
http://tirania.org/blog/archive/2008/Nov-05.html
Miguel has other posts on AOT details too.
I am a newbie to embedded developement, as figure shown. I have a small ARM board, AT91SAM7-EX256. I have also a JTAG programmer dongle, too. I am using Linux (Ubuntu x86_32) on my notebook and desktop machine. I'm using CodeSourcery Lite for cross-compiling to ARM-Linux.
Am I right that I can't use this Linux-target cross-compiler to make binary or hex files for the small ARM board (it comes without any operating system)? Should I use the version called ARM EABI instead?
As I see, it's a "generic" ARM compiler. I've read some docs, and there're lot of options to specify the processor type and instruction set (thumb, etc.), there will be no problem with it. But how can I tell the compiler, how should the image (bin/hex) looks like for the specific board (startup, code/data blocks etc.)? (In assemblers, there're the org and load directives for it.)
What software do I need to capture some debug messages from the board on my PC? I don't want to on-board debugging, I just need some detailed run-time signal, more than just blinking leds.
I have an option to use MS-Windows, I can get a dedicated machine for it. Do you recommend it, is it much easier?
Can I use inline assembly somehow in my C code? I dunno anything about that. Can I use C++ or just C?
I have also a question, which don't need to answer: are there really 4096 kind of GNU compilers and cross-compilers (from Linux_x86_32 -> Linux_x86_32, Linux_x86_32 -> Linux_ARM, OSX -> Linux_ARM, PPC_Linux -> OSX) and 16 different GNU compiler sources (as many target platforms/processors exists) around? The signs says "yes", but I can't believe it. Correct me, and show me the GNU compiler which can produce object file for any platform/processor, and the universal linker which can produce executable for any platform.
While Windows is not a "better" platform do this kind of embedded development on, it may be easier to start with since you can get a pre-built environment to work with. For example, Yagarto (which I would recommend).
Setting up an embedded development environment on Linux can require a considerable amount of knowledge, but it's not impossible.
To answer your questions:
Your Linux cross-compiler comes with libraries to build executables for a Linux environment. You have hinted that you want to build a bare-metal executable for this board. While you can do this with your compiler, it will just confuse things. I recommend building a baremetal cross-compiler. Since you're building your own baremetal executable (and thus you are the operating system, the ABI doesn't matter since you're generating all of the code and not interoperating with other previously built code.
There are several versions of the ARM instruction set (and Thumb). You need to generate code for your particular processor. If you generate the code for a newer version of the instruction set, you will likely generate code which generates a reserved instruction exception. Most prebuilt gcc cross-compiler toolchains for ARM are "multilib" and will build for a variety of architectures in both ARM and Thumb.
Not sure exactly what you're looking for here. This is a bare metal platform. You can use the debugger channel to send messages if you're debugging on target, or you'll need to build your own communication channel into the firmware you write (i.e. uart support).
See above.
Yes. See here for details on gcc's extended inline assembly syntax. You can do this in C++ and C. You can also simply link pure assembly files.
There is no universal gcc compiler / linker. You need a uniquely built compiler for each host / target combination you use.
Finally, please take a look at Atmel's documentation. They have a wealth of information on developing for this target as well as a board package with the needed linker directives and example programs. Note of course the package is for Atmel's own eval board, but it will get you started.
http://sam7stuff.blogspot.com/
I use either of the codesourcery lite versions. But I have no use for the gcc library nor a C library, I just need a compiler.
In the gcc 3 days newlib was great, modify two files worth of system support (simple open, close, read, putc type stuff) and you could compile just about anything, but with gcc 4.x you cannot even go back and cross compile gcc 3.x, you have to install an old linux distro in a virtual machine.
To get the gcc library yes you probably want to use the eabi version not the version with linux gnueabi in the file names.
You might also consider llvm (if you dont need a C library, and you will still need binutils), hmm, I wonder if newlib compiles with llvm.
I prefer to avoid getting trapped in sandboxes, learn the tools and how to manipulate the linker, etc to build your binaries.
I'm aware of the existence of libobjc2, and I gather that I'll need to use clang rather than GCC, but I can't find any basic instructions of what's different about the compilation process.
Can anyone give explicit, step-by-step instructions on acquiring, configuring, compiling, and using GNUstep with Objective-C 2.0 in Ubuntu?
Since the GNUStep ObjC2 FAQ has already been referenced, I'll assume you've had a look. I would like to point this out, however:
For more advanced features, currently only supported if you compile with Clang, you will need the GNUstep runtime. This is not currently considered production ready. It should work as a drop-in replacement for the GCC runtime, but some of the advanced features are not well-tested.
The FAQ also calls out the following:
If you are using a recent version of GCC to compile your code then you should have a copy of the Objective-C runtime library that came with your compiler.
If you compile with the -fobjc-nonfragile-abi flag then you will use the new ABI. This is only supported with the GNUstep runtime. This adds:
Property introspection
Introspection on optional protocol methods
Non-fragile instance variables
Forwarding proxy support
So, if you're looking for older functionality via GCC, this tutorial would do the job nicely, as would this one. You've explicitly called out that you're looking to do this with the functionality provided by Clang (via libobjc2), which has its own bed of documentation.
Obtaining a release of Clang and getting set up seems fairly cut and dried. The LLVM Getting Started document is exceptionally robust (full documentation archive here), which should provide insight into getting the backend set up and compiling properly. Some additional insight into the expected build procedure can be found here.
However, compiling an Objective-C application in Clang seems extremely underdocumented and untested at the time of this writing. As features become available and the codebase stabilizes, I imagine more user documentation will go live.
According to the GNUstep Wiki, you need just need to compile your code with -fblocks and -fobjc-nonfragile-abi. Then you just use the language features in your code.
I'm currently trying to get g++ working, and looking at http://gcc.gnu.org/install/build.html, I can't seem to find where it says how "to perform a 3-stage bootstrap of the compiler". Where would I find this information?
(I'm on a mac, in case that matters.)
After running configure, you do make bootstrap
You cannot bootstrap GCC without an already-functioning compiler on your platform:
From the prerequisites page:
ISO C90 compiler
Necessary to bootstrap GCC, although versions of GCC prior to 3.4 also allow bootstrapping with a traditional (K&R) C compiler.
And to preempt your next question, you also need a functioning compiler (usually GCC) in order to build Clang+LLVM.
It might be possible to do what you're trying so hard to do, by cross-compiling GCC from some other platform (see this section of the documentation). But I imagine this is not for the feint of heart, and you'd be far, far better off simply updating your copy of Mac OS X to the latest version with Xcode support.
From that link:
For a native build, the default configuration is to perform a 3-stage bootstrap of the compiler when `make' is invoked.
It seems to me that if your configuration isn't tweaked, it should do it out of the box. Just type make.
More specifically, you have to download the source code, and follow the instructions in that whole tutorial in order to build.
A side note - I am finding it hard to believe that there is no easy way to get GCC on an OSX box without having the installation media. That sounds really annoying :)
Edit:
If you are simply trying to write C++ on OSX, you could install one of many other IDEs. If you are lucky, they may come with their own compiler. Here is a list of alternatives to XCode:
http://alternativeto.net/desktop/xcode/?profile=mac&platform=mac