llvm-project

d6bfe10a - [Darwin][Driver][clang] apple-none-macho orders the resource directory after internal-externc-isystem when nostdlibinc is used (#122035)

[Darwin][Driver][clang] apple-none-macho orders the resource directory after internal-externc-isystem when nostdlibinc is used (#122035) Embedded development often needs to use a different C standard library, replacing the existing one normally passed as -internal-externc-isystem. This works fine for an apple-macos target, but apple-none-macho doesn't work because the MachO driver doesn't implement AddClangSystemIncludeArgs to add the resource directory as -internal-isystem like most other drivers do. Move most of the search path logic from Darwin and DarwinClang down into an AppleMachO toolchain between the MachO and Darwin toolchains. Also define __MACH__ for apple-none-macho, as Swift expects all MachO targets to have that defined.