я не могу скомпилировать с arm-none-eabi-gcc

Question

Я пытаюсь скомпилировать код с arm-none-eabi-gcc, но я получаю следующие ошибки. Может ли кто-нибудь мне помочь или объяснить, в чем причина?

Спасибо!

/usr/lib/gcc/arm-none-eabi/4.9.3/../../../arm-none-eabi/lib/libc.a(lib_a-exit.o): In function `exit':
/build/newlib-5zwpxE/newlib-2.2.0+git20150830.5a3d536/build/arm-none-eabi/newlib/libc/stdlib/../../../../../newlib/libc/stdlib/exit.c:70: undefined reference to `_exit'
/usr/lib/gcc/arm-none-eabi/4.9.3/../../../arm-none-eabi/lib/libc.a(lib_a-fstatr.o): In function `_fstat_r':
/build/newlib-5zwpxE/newlib-2.2.0+git20150830.5a3d536/build/arm-none-eabi/newlib/libc/reent/../../../../../newlib/libc/reent/fstatr.c:62: undefined reference to `_fstat'
/usr/lib/gcc/arm-none-eabi/4.9.3/../../../arm-none-eabi/lib/libc.a(lib_a-openr.o): In function `_open_r':
/build/newlib-5zwpxE/newlib-2.2.0+git20150830.5a3d536/build/arm-none-eabi/newlib/libc/reent/../../../../../newlib/libc/reent/openr.c:59: undefined reference to `_open'
/usr/lib/gcc/arm-none-eabi/4.9.3/../../../arm-none-eabi/lib/libc.a(lib_a-sbrkr.o): In function `_sbrk_r':
/build/newlib-5zwpxE/newlib-2.2.0+git20150830.5a3d536/build/arm-none-eabi/newlib/libc/reent/../../../../../newlib/libc/reent/sbrkr.c:58: undefined reference to `_sbrk'
/usr/lib/gcc/arm-none-eabi/4.9.3/../../../arm-none-eabi/lib/libc.a(lib_a-writer.o): In function `_write_r':
/build/newlib-5zwpxE/newlib-2.2.0+git20150830.5a3d536/build/arm-none-eabi/newlib/libc/reent/../../../../../newlib/libc/reent/writer.c:58: undefined reference to `_write'
/usr/lib/gcc/arm-none-eabi/4.9.3/../../../arm-none-eabi/lib/libc.a(lib_a-closer.o): In function `_close_r':
/build/newlib-5zwpxE/newlib-2.2.0+git20150830.5a3d536/build/arm-none-eabi/newlib/libc/reent/../../../../../newlib/libc/reent/closer.c:53: undefined reference to `_close'
/usr/lib/gcc/arm-none-eabi/4.9.3/../../../arm-none-eabi/lib/libc.a(lib_a-isattyr.o): In function `_isatty_r':
/build/newlib-5zwpxE/newlib-2.2.0+git20150830.5a3d536/build/arm-none-eabi/newlib/libc/reent/../../../../../newlib/libc/reent/isattyr.c:58: undefined reference to `_isatty'
/usr/lib/gcc/arm-none-eabi/4.9.3/../../../arm-none-eabi/lib/libc.a(lib_a-lseekr.o): In function `_lseek_r':
/build/newlib-5zwpxE/newlib-2.2.0+git20150830.5a3d536/build/arm-none-eabi/newlib/libc/reent/../../../../../newlib/libc/reent/lseekr.c:58: undefined reference to `_lseek'
/usr/lib/gcc/arm-none-eabi/4.9.3/../../../arm-none-eabi/lib/libc.a(lib_a-readr.o): In function `_read_r':
/build/newlib-5zwpxE/newlib-2.2.0+git20150830.5a3d536/build/arm-none-eabi/newlib/libc/reent/../../../../../newlib/libc/reent/readr.c:58: undefined reference to `_read'

Answer 1

Поскольку вы компилируете для цели с «голым железом», newlib по умолчанию не обеспечивает реализации функций, которые имеют смысл только в системе с консолью и жестким диском, например, в основном с системными вызовами, такими как * 1002. * / write / open / close / ...

Если вам не нужны эти функции, использование опции --specs=nosys.specs сделает ваше приложение ссылкой по умолчанию, в основном пустые реализации при вызове будет возвращен код ошибки:

/opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/arm-none-eabi-gcc -o hello hello.c
/opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/bin/ld: /opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/lib/libc.a(lib_a-exit.o): in function `exit':
/tmp/dgboter/bbs/rhev-vm10--rhe6x86_64/buildbot/rhe6x86_64--arm-none-eabi/build/src/newlib-cygwin/newlib/libc/stdlib/exit.c:64: undefined reference to `_exit'
/opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/bin/ld: /opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/lib/libc.a(lib_a-sbrkr.o): in function `_sbrk_r':
/tmp/dgboter/bbs/rhev-vm10--rhe6x86_64/buildbot/rhe6x86_64--arm-none-eabi/build/src/newlib-cygwin/newlib/libc/reent/sbrkr.c:51: undefined reference to `_sbrk'
/opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/bin/ld: /opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/lib/libc.a(lib_a-writer.o): in function `_write_r':
/tmp/dgboter/bbs/rhev-vm10--rhe6x86_64/buildbot/rhe6x86_64--arm-none-eabi/build/src/newlib-cygwin/newlib/libc/reent/writer.c:49: undefined reference to `_write'
/opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/bin/ld: /opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/lib/libc.a(lib_a-closer.o): in function `_close_r':
/tmp/dgboter/bbs/rhev-vm10--rhe6x86_64/buildbot/rhe6x86_64--arm-none-eabi/build/src/newlib-cygwin/newlib/libc/reent/closer.c:47: undefined reference to `_close'
/opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/bin/ld: /opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/lib/libc.a(lib_a-lseekr.o): in function `_lseek_r':
/tmp/dgboter/bbs/rhev-vm10--rhe6x86_64/buildbot/rhe6x86_64--arm-none-eabi/build/src/newlib-cygwin/newlib/libc/reent/lseekr.c:49: undefined reference to `_lseek'
/opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/bin/ld: /opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/lib/libc.a(lib_a-readr.o): in function `_read_r':
/tmp/dgboter/bbs/rhev-vm10--rhe6x86_64/buildbot/rhe6x86_64--arm-none-eabi/build/src/newlib-cygwin/newlib/libc/reent/readr.c:49: undefined reference to `_read'
/opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/bin/ld: /opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/lib/libc.a(lib_a-fstatr.o): in function `_fstat_r':
/tmp/dgboter/bbs/rhev-vm10--rhe6x86_64/buildbot/rhe6x86_64--arm-none-eabi/build/src/newlib-cygwin/newlib/libc/reent/fstatr.c:55: undefined reference to `_fstat'
/opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/bin/ld: /opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/lib/libc.a(lib_a-isattyr.o): in function `_isatty_r':
/tmp/dgboter/bbs/rhev-vm10--rhe6x86_64/buildbot/rhe6x86_64--arm-none-eabi/build/src/newlib-cygwin/newlib/libc/reent/isattyr.c:52: undefined reference to `_isatty'
$

Использование опции --specs=nosys.specs:

/opt/arm/9/gcc-arm-9.2-2019.12-x86_64-arm-none-eabi/bin/arm-none-eabi-gcc --specs=nosys.specs -o hello hello.c 
$

Альтернатива, если вы хотите иметь собственную реализацию этих отсутствующих системных вызовов , состоит в том, чтобы создать свой собственный минимальный syscalls.c из исходного файла newlib libgloss/arm/syscalls.c: вы можете реализовать некоторые системные вызовы, и пометить другие, которые вам не нужны. newlib исходный код можно просмотреть с здесь , и см. Раздел 12 System Calls и 12.1 Definitions for OS interface newlib документации для получения более подробной информации.