Doc building for ios

There are two possible routes for writing code in Rust for iOS:

• either let Rust generate LLVM bitcode and use that using the Xcode toolchain
• or try to add cross-compilation support to Rust.

a) LLVM Bitcode

See https://github.com/shilgapira/ObjCrust

b) Cross-compiler

Some issues need to be resolved yet, see the open issues.

You need XCode 5.

1. Build Rust:

mkdir build_ios; cd build_ios
../configure --target=arm-apple-darwin
make VERBOSE=1

1. Use Rust:

rustc --target=arm-apple-darwin foo.rs

Adjustments

Current adjustments

For the current adjustments:

• see for arm-apple-darwin in mk/platform.mk
• see for apple-darwin in mk/rt.mk
• in the source files grep for __APPLE__

Possible future adjustments

• Compilation:
  • Compile twice, with both -arch armv7 and -arch armv7s (A6 processor) ?
    • See https://github.com/ghc-ios/ghc-ios-scripts/blob/master/arm-apple-darwin10-clang
• Code:
  • src/librustc/back/arm.rs
  • src/rt/arch/arm/record_sp.S

Resources

• ARM Machine Directives:
• Building a GHC cross-compiler for Apple iOS targets
• CMOSS: scripts for building cross-platform c/c++ open source software libraries for iOS and Android.
• Cross-compilation using Clang
• Doc building for android
• environ.7: _NSGetEnviron()
• iOS ABI Function Call Guide
• llc
• llvm-dis
• Note seeing LLVM output from rust