Hi, I'm trying to build Boost from Linux for Windows. I created user-config.jam file with the following content: using gcc : mingw : x86_64-w64-mingw32-g++ : <rc>x86_64-w64-mingw32-windres <as>x86_64-w64-mingw32-as ; I build using this command line: ./b2 --user-config=./user-config.jam --prefix=$HOME/boost-1.82.0 target-os=windows address-model=64 variant=release install but I get these messages when building boost.context: gcc.compile.asm bin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden/asm/ontop_x86_64_sysv_elf_gas.o ontop_x86_64_sysv_elf_gas.S: Assembler messages: ontop_x86_64_sysv_elf_gas.S:43: Warning: .type pseudo-op used outside of .def/.endef: ignored. ontop_x86_64_sysv_elf_gas.S:43: Error: junk at end of line, first unrecognized character is `o' libs/context/src/asm/ontop_x86_64_sysv_elf_gas.S:135: Warning: .size pseudo-op used outside of .def/.endef: ignored. libs/context/src/asm/ontop_x86_64_sysv_elf_gas.S:135: Error: junk at end of line, first unrecognized character is `o' libs/context/src/asm/ontop_x86_64_sysv_elf_gas.S:138: Error: junk at end of line, first unrecognized character is `-' "x86_64-w64-mingw32-g++" -x assembler-with-cpp -m64 -mthreads -O3 -finline-functions -Wno-inline -Wall -fvisibility=hidden -DBOOST_ALL_NO_LIB=1 -DBOOST_CONTEXT_SOURCE -DBOOST_DISABLE_ASSERTS -DNDEBUG -D_WIN32_WINNT=0x0601 -I"." -c -o "bin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden/asm/ontop_x86_64_sysv_elf_gas.o" "libs/context/src/asm/ontop_x86_64_sysv_elf_gas.S" ...failed gcc.compile.asm bin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden/asm/ontop_x86_64_sysv_elf_gas.o... gcc.compile.asm bin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden/asm/make_x86_64_sysv_elf_gas.o make_x86_64_sysv_elf_gas.S: Assembler messages: make_x86_64_sysv_elf_gas.S:44: Warning: .type pseudo-op used outside of .def/.endef: ignored. make_x86_64_sysv_elf_gas.S:44: Error: junk at end of line, first unrecognized character is `m' libs/context/src/asm/make_x86_64_sysv_elf_gas.S:144: Warning: .size pseudo-op used outside of .def/.endef: ignored. libs/context/src/asm/make_x86_64_sysv_elf_gas.S:144: Error: junk at end of line, first unrecognized character is `m' libs/context/src/asm/make_x86_64_sysv_elf_gas.S:147: Error: junk at end of line, first unrecognized character is `-' "x86_64-w64-mingw32-g++" -x assembler-with-cpp -m64 -mthreads -O3 -finline-functions -Wno-inline -Wall -fvisibility=hidden -DBOOST_ALL_NO_LIB=1 -DBOOST_CONTEXT_SOURCE -DBOOST_DISABLE_ASSERTS -DNDEBUG -D_WIN32_WINNT=0x0601 -I"." -c -o "bin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden/asm/make_x86_64_sysv_elf_gas.o" "libs/context/src/asm/make_x86_64_sysv_elf_gas.S" ...failed gcc.compile.asm bin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden/asm/make_x86_64_sysv_elf_gas.o... gcc.compile.asm bin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden/asm/jump_x86_64_sysv_elf_gas.o jump_x86_64_sysv_elf_gas.S: Assembler messages: jump_x86_64_sysv_elf_gas.S:44: Warning: .type pseudo-op used outside of .def/.endef: ignored. jump_x86_64_sysv_elf_gas.S:44: Error: junk at end of line, first unrecognized character is `j' libs/context/src/asm/jump_x86_64_sysv_elf_gas.S:139: Warning: .size pseudo-op used outside of .def/.endef: ignored. libs/context/src/asm/jump_x86_64_sysv_elf_gas.S:139: Error: junk at end of line, first unrecognized character is `j' libs/context/src/asm/jump_x86_64_sysv_elf_gas.S:142: Error: junk at end of line, first unrecognized character is `-' "x86_64-w64-mingw32-g++" -x assembler-with-cpp -m64 -mthreads -O3 -finline-functions -Wno-inline -Wall -fvisibility=hidden -DBOOST_ALL_NO_LIB=1 -DBOOST_CONTEXT_SOURCE -DBOOST_DISABLE_ASSERTS -DNDEBUG -D_WIN32_WINNT=0x0601 -I"." -c -o "bin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden/asm/jump_x86_64_sysv_elf_gas.o" "libs/context/src/asm/jump_x86_64_sysv_elf_gas.S" ...failed gcc.compile.asm bin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden/asm/jump_x86_64_sysv_elf_gas.o... ...skipped <pbin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden>libboost_context.a(clean) for lack of <pbin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden>asm/make_x86_64_sysv_elf_gas.o... ...skipped <pbin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden>libboost_context.a for lack of <pbin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden>asm/make_x86_64_sysv_elf_gas.o... ...skipped <p/home/andrew/boost-1.82.0/lib>libboost_context.a for lack of <pbin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden>libboost_context.a... ...skipped <pbin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden>libboost_context-variant-static.cmake for lack of <pbin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden>libboost_context.a... ...skipped <p/home/andrew/boost-1.82.0/lib/cmake/boost_context-1.82.0>libboost_context-variant-static.cmake for lack of <pbin.v2/libs/context/build/gcc-mingw/release/link-static/target-os-windows/threading-multi/visibility-hidden>libboost_context-variant-static.cmake... ...failed updating 3 targets... ...skipped 5 targets... any ideas how can I fix it? best!