X-Git-Url: http://git.monstr.eu/?p=linux-2.6-microblaze.git;a=blobdiff_plain;f=Documentation%2Fkbuild%2Fllvm.rst;h=d32616891dcfb23dd2a77e525ab316502c501a3f;hp=b18401d2ba8204bb66551f5e5c67bc22c13a52f4;hb=1791596be2723f01de2f69d16a422fdba182c706;hpb=09d78dde88ef95a27b54a6e450ee700ccabdf39d diff --git a/Documentation/kbuild/llvm.rst b/Documentation/kbuild/llvm.rst index b18401d2ba82..d32616891dcf 100644 --- a/Documentation/kbuild/llvm.rst +++ b/Documentation/kbuild/llvm.rst @@ -38,7 +38,7 @@ Cross Compiling A single Clang compiler binary will typically contain all supported backends, which can help simplify cross compiling. :: - ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- make CC=clang + make ARCH=arm64 CC=clang CROSS_COMPILE=aarch64-linux-gnu- ``CROSS_COMPILE`` is not used to prefix the Clang compiler binary, instead ``CROSS_COMPILE`` is used to set a command line flag: ``--target=``. For @@ -60,8 +60,27 @@ They can be enabled individually. The full list of the parameters: :: OBJCOPY=llvm-objcopy OBJDUMP=llvm-objdump READELF=llvm-readelf \ HOSTCC=clang HOSTCXX=clang++ HOSTAR=llvm-ar HOSTLD=ld.lld -Currently, the integrated assembler is disabled by default. You can pass -``LLVM_IAS=1`` to enable it. +The integrated assembler is enabled by default. You can pass ``LLVM_IAS=0`` to +disable it. + +Omitting CROSS_COMPILE +---------------------- + +As explained above, ``CROSS_COMPILE`` is used to set ``--target=``. + +If ``CROSS_COMPILE`` is not specified, the ``--target=`` is inferred +from ``ARCH``. + +That means if you use only LLVM tools, ``CROSS_COMPILE`` becomes unnecessary. + +For example, to cross-compile the arm64 kernel:: + + make ARCH=arm64 LLVM=1 + +If ``LLVM_IAS=0`` is specified, ``CROSS_COMPILE`` is also used to derive +``--prefix=`` to search for the GNU assembler and linker. :: + + make ARCH=arm64 LLVM=1 LLVM_IAS=0 CROSS_COMPILE=aarch64-linux-gnu- Supported Architectures ----------------------- @@ -111,9 +130,10 @@ Getting Help ------------ - `Website `_ -- `Mailing List `_: +- `Mailing List `_: +- `Old Mailing List Archives `_ - `Issue Tracker `_ -- IRC: #clangbuiltlinux on chat.freenode.net +- IRC: #clangbuiltlinux on irc.libera.chat - `Telegram `_: @ClangBuiltLinux - `Wiki `_ - `Beginner Bugs `_