LLVM Cross-Compiler: Difference between revisions
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-march=armv7-a -mfloat-abi=soft -ccc-host-triple arm-elf
</source>
JamesM@osdev.forum wrote:
Or since 3.1 you can just shorten this to:
<source lang="bash">
-target armv7--eabi -mcpu=cortex-a9
</source>
It is recommended to build post-3.1 clang as there are some crash bugs fixed.
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Revision as of 16:20, 22 September 2012
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Advanced |
EDIT: A mostly working Clang cross-compiler is generated by this buildscript. Dissect it to learn more. TODO: move details to this page.
Is as simple as that:
mkdir crossllvm
cd crossllvm
svn co http://llvm.org/svn/llvm-project/llvm/trunk llvm
cd llvm/tools
svn co http://llvm.org/svn/llvm-project/cfe/trunk clang
cd ../..
mkdir build
cd build
cmake ../llvm
make
After building you will have a compiler able to output multiple output formats regardless of your current platform, you can specify x86 ELF output format (for example) to clang using "-ccc-host-triple i686-pc-linux-gnu".
TODO: beware that clang is both a cross-compiler and a host-compiler and you would have to specify some options to disable host functionality.
TODO: clang requires a fairly recent version of binutils to work, try 2.21 or above if you get assembly compilation errors.
TODO: describe non-svn build from released tarballs.
TODO: integrate libc++ build instructions
pitfall@osdev.forum wrote:
As far as I know, you can use -ccc-host-triple <your target output format> option with -march=<your target architecture> to cross-compile with LLVM. It's been a while since I used LLVM/CLang, but I think this'll work with some investigation.
Here's an example quoted for some obscure mailing lists illustrating what I wrote :
-march=armv7-a -mfloat-abi=soft -ccc-host-triple arm-elf
JamesM@osdev.forum wrote:
Or since 3.1 you can just shorten this to:
-target armv7--eabi -mcpu=cortex-a9
It is recommended to build post-3.1 clang as there are some crash bugs fixed.