Re: [Boost-users] [Boost.build] Building for ARM64

Subject: Re: [Boost-users] [Boost.build] Building for ARM64
From: Vladimir Prus (vladimir_at_[hidden])
Date: 2015-01-13 07:42:57

On 01/13/2015 03:15 PM, mefyl wrote:
> Hi,
>
> In my quest cross-compiling Boost.Context for ARM64, I encounter the following
> problem (using develop since ARM64 support is not in 1.57):
>
> $ ./bootstrap.sh --with-libraries=context
> [...]
> $ ./b2 -d2 -q toolset=clang architecture=arm abi=aapcs address-model=64
> binary-format=mach-o
> [...]
> "clang++"   -o "bin.v2/libs/system/build/clang-darwin-4.2.1/release/abi-
> aapcs/address-model-64/architecture-arm/threading-multi/libboost_system.dylib"
> -single_module -dynamiclib -install_name "libboost
> _system.dylib" "bin.v2/libs/system/build/clang-darwin-4.2.1/release/abi-
> aapcs/address-model-64/architecture-arm/threading-multi/error_code.o"
>
> Despite asking for arm, the "-arch arm64" I would expect is not passed to
> clang which thus compile to x86_64. However Boost.Context DOES understand I'm
> targeting arm since it picks the right ASM file:
>
>      "clang++" -x assembler-with-cpp -O3 -O3 -finline-functions -Wno-inline -
> Wall -fPIC -DBOOST_ALL_NO_LIB=1 -DBOOST_CHRONO_DYN_LINK=1 -
> DBOOST_CONTEXT_DYN_LINK=1 -DBOOST_CONTEXT_SOURCE -DBOOST_SYSTEM_DYN_LINK=1 -
> DBOOST_SYSTEM_NO_DEPRECATED -DBOOST_THREAD_BUILD_DLL=1 -DBOOST_THREAD_POSIX -
> DBOOST_THREAD_USE_DLL=1 -DNDEBUG -I"." -c -o "bin.v2/libs/context/build/clang-
> darwin-4.2.1/release/abi-aapcs/address-model-64/architecture-arm/threading-
> multi/asm/make_arm64_aapcs_macho_gas.o"
> "libs/context/src/asm/make_arm64_aapcs_macho_gas.S"
>
> Which yields assembly errors of course since "-arch arm64" is not passed.
>
> Other sources seem to manage to build Boost for ARM64 using darwin toolset
> forcing clang as the compiler and passing many additional options, but their
> setup fails to build Boost.Context since it either picks the wrong ASM file,
> either complains the platform is not supported.

Hi Quentin,

it does not appear that anybody made clang-darwing.jam do anything about architecture
or address-model features. Would the following patch work for you?

diff --git a/src/tools/clang-darwin.jam b/src/tools/clang-darwin.jam
index 51e5fad..2976030 100644
--- a/src/tools/clang-darwin.jam
+++ b/src/tools/clang-darwin.jam
@@ -72,6 +72,8 @@ rule init ( version ? :  command * : options * )

  SPACE = " " ;

+flags clang-darwing OPTIONS <architecture>arm <address-model>64 : -arch arm64 ;
+
  flags clang-darwin.compile OPTIONS <cflags> ;
  flags clang-darwin.compile.c++ OPTIONS <cxxflags> ;
  # flags clang-darwin.compile INCLUDES <include> ;

-- 
Vladimir Prus
CodeSourcery / Mentor Embedded
http://vladimirprus.com