This directory contains integration tests written in Objective-C. They're compiled to an ARMv6 Mach-O binary and packaged into a bundle (TestApp.app) so that they can be run in the emulator like a normal iPhone OS app. The code in integration.rs lets them be run by cargo test (which also runs unit tests written in Rust).
Upstream LLVM is needed for building the ARMv6 test binary. 32-bit iOS support is broken in version 13 onwards, so 12.0.1 is the newest supported version you can use. Downloads:
- LLVM 12.0.1 Windows x64 release binaries (extract it with 7-zip)
- LLVM 12.0.0 macOS x64 release binaries (extract it with
tar -xf) - Other versions (though you might need to build LLVM yourself, sorry :c)
Extract LLVM to tests/llvm, so that e.g. tests/TestApp_build/llvm/bin/clang (with .exe suffix, on Windows) is the path to Clang. cargo test (via integration.rs) will do the rest.
32-bit iOS is an awkward platform to target. There's no way Apple's official tools still support it, and nobody wants to have to install an old version of an OS X in a VM. Also, this is a cross-platform emulation project, but Apple's tools require you to own a Mac. Using LLVM lets us avoid a dependency on this legacy, proprietary software that only runs on one platform, in favour of somewhat less legacy (July 2021), cross-platform software with convenient release builds available.
Upstream LLVM provides a compiler (Clang) and linker (LLD) that can target 32-bit iOS, but not platform headers or libraries, so some tricks are needed. See the comments in integration.rs and main.c. Some additional notes:
- The resulting binary is probably not actually compatible iPhone OS 2. It uses
LC_MAINrather thanLC_UNIX_THREAD. It might work on iOS 6? I haven't tested it. - LLD crashes if you try to compile Objective-C rather than C code. It might be expecting an Objective-C system library.