* Use gcc and g++ rather than cc and c++, as the latter now point to
clang with recent Xcode versions and compilation of the host tools
fail for various reasons with it.
* Replace the case-sensitive filesystem check with a more basic one,
as diskutil no longer supports the behaviour of getting info for the
volume that any path is on.
* Updated ReadMe with a correct list of prerequisites for OS X.
* GCC 2 builds are still broken due to a strange error that only
occurs with a GCC 2 built on OS X 10.7
Will be merged with the x86 one later on. Requires -fno-omit-frame-pointer on
the kernel build flags, GCC defaults to not generating stack frames on x86_64.
Since x86 and x86_64 share a lot of common code, x86_64 kernel sources/headers
are going to reside under headers/private/kernel/arch/x86 and
src/system/kernel/arch/x86 along with the existing x86 code. This commit
changes the build system to handle this. A new variable, TARGET_KERNEL_ARCH,
has been added. This is the name of the kernel/boot architecture directory
name, set to x86 on both x86 and x86_64. This is now used in all places where
TARGET_ARCH was used to get to kernel arch sources/headers (I've changed
everything necessary as far as I can tell). Kernel won't build for x86_64
at the moment as the sources have not been merged, loader does.
* platform_allocate_elf_region() is removed, it is implemented in platform-
independent code now (ELF*Class::AllocateRegion). For ELF64 it is now
assumed that 64-bit addresses are mapped in the loader's 32-bit address space
as (address - KERNEL_BASE_64BIT + KERNEL_BASE).
* mapped_delta field from preloaded_*_image removed, now handled compile-time
using the ELF*Class::Map method.
* Also link the kernel with -z max-page-size=0x1000, removes the need for
2MB alignment on the data segment (not going to map the kernel with large
pages for the time being).
* set_haiku_revision doesn't currently support ELF64, don't use a
revisioned kernel image on x86_64 for now.
* Don't try to build add-ons for x86_64 yet.
The red zone is a 128-byte area below the stack pointer specified by the
AMD64 ABI that can be used by leaf functions for their stack frame without
modifying the stack pointer. It is guaranteed not to be modified by signal
handlers. This cannot be used in kernel mode code, as an interrupt handler
could overwrite it, so stop GCC from generating code that uses it.
* our current gcc can't be built with multilib for ppc anyway,
* this allows going further on real hardware, though dprintf() sends wrong data to the serial port.
* x86_64 is using the existing *_ia32 boot platforms.
* Special flags are required when compiling the loader to get GCC to compile
32-bit code. This adds a new set of rules for compiling boot code rather
than using the kernel rules, which compile using the necessary flags.
* Some x86_64 private headers have been stubbed by #include'ing the x86
versions. These will be replaced later.
