Bitcode is a compile-time feature (not a link-time feature) which means that every .o file should contain an extra section called __bitcode when built with bitcode. You can confirm whether your binary is bitcode-compatible by running otool -l (my .o or .a file) | grep __LLVM. When you build normally, Xcode adds the build flag … Read more
Given some C/C++ file foo.c: > clang -S -emit-llvm foo.c Produces foo.ll which is an LLVM IR file. The -emit-llvm option can also be passed to the compiler front-end directly, and not the driver by means of -cc1: > clang -cc1 foo.c -emit-llvm Produces foo.ll with the IR. -cc1 adds some cool options like -ast-print. … Read more
When building static libraries you must add the following for bitcode generation: -fembed-bitcode for a dynamic library you need to additionally link with -fembed-bitcode Note: This command is only available with Xcode7+ In regards to the accepted answer of using -fembed-bitcode-marker You should be aware that a normal build with the -fembed-bitcode-marker option will produce … Read more
What does the ENABLE_BITCODE actually do, will it be a non-optional requirement in the future? I’m not sure at what level you are looking for an answer at, so let’s take a little trip. Some of this you may already know. When you build your project, Xcode invokes clang for Objective-C targets and swift/swiftc for … Read more
Bitcode refers to to the type of code: “LLVM Bitcode” that is sent to iTunes Connect. This allows Apple to use certain calculations to re-optimize apps further (e.g: possibly downsize executable sizes). If Apple needs to alter your executable then they can do this without a new build being uploaded. This differs from: Slicing which … Read more
Your library was compiled without bitcode, but the bitcode option is enabled in your project settings. Say NO to Enable Bitcode in your target Build Settings and the Library Build Settings to remove the warnings. For those wondering if enabling bitcode is required: For iOS apps, bitcode is the default, but optional. For watchOS and … Read more