CONFIG_THREAD_LOCAL_STORAGE=y build fails with ZEPHYR_TOOLCHAIN_VARIANT=gnuarmemb

[pfalcon]

ZEPHYR_TOOLCHAIN_VARIANT=gnuarmemb is one of the supported toolchains to build Zephyr (for ARM architecture). After #28982 was merged, and with CONFIG_THREAD_LOCAL_STORAGE enabled (which it is, for one sanitycheck configuration of tests/kernel/common), the build fails with:

[ 87%] Linking C executable app_smem_unaligned_prebuilt.elf
/home/buildslave/srv/toolchain/gcc-arm-none-eabi-9-2019-q4-major/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/bin/ld: /home/buildslave/srv/toolchain/gcc-arm-none-eabi-9-2019-q4-major/bin/../lib/gcc/arm-none-eabi/9.2.1/thumb/v7e-m/nofp/libgcc.a(emutls.o): in function `emutls_alloc':
emutls.c:(.text+0x5a): undefined reference to `abort'
/home/buildslave/srv/toolchain/gcc-arm-none-eabi-9-2019-q4-major/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/bin/ld: /home/buildslave/srv/toolchain/gcc-arm-none-eabi-9-2019-q4-major/bin/../lib/gcc/arm-none-eabi/9.2.1/thumb/v7e-m/nofp/libgcc.a(emutls.o): in function `__emutls_get_address':
emutls.c:(.text+0x7a): undefined reference to `abort'
collect2: error: ld returned 1 exit status
make[2]: *** [zephyr/app_smem_unaligned_prebuilt.elf] Error 1
make[1]: *** [zephyr/CMakeFiles/app_smem_unaligned_prebuilt.dir/all] Error 2
make: *** [all] Error 2

INFO    - /home/buildslave/srv/zephyr/master/gnuarmemb/frdm_k64f/frdm_k64f/tests/kernel/common/kernel.common.tls/build.log

Full build log: https://ci.linaro.org/job/zephyr-upstream/PLATFORM=frdm_k64f,ZEPHYR_TOOLCHAIN_VARIANT=gnuarmemb,label=docker-xenial-amd64-13/5680/console

[pfalcon]

@galak: FYI

[pfalcon]

This error doesn't happen if built with CONFIG_NEWLIB_LIBC=y, which leads us to the patch #29542.

Note that I didn't try to investigate why emutls.c "the emulation of thread local storage using malloc()" https://github.com/gcc-mirror/gcc/blob/master/libgcc/emutls.c is being used. @galak, let me know if you think that should be investigated.

[galak]

@dcpleung fyi

[galak]

since this is the case w/minlibc that fails, its odd to me that this works ok w/Zephyr SDK & fails w/gnuarmemb.

[pfalcon]

Apparently, some implicitly linked libs included with Zephyr SDK provide abort().

[galak]

Apparently, some implicitly linked libs included with Zephyr SDK provide abort().

looking at the error message in more detail, I see this is in libgcc, so that partially explains it.

[galak]

Based on https://github.com/ARM-software/toolchain-gnu-bare-metal/blob/365499ead3c18e9c1a70880c34d8efe08549df3c/build-toolchain.sh#L423 we should probably change things so TLS is only supported w/Zephyr toolchain.

[dcpleung]

Submitted #29591 to limit the kconfig option to Zephyr SDK only. Hopefully that fixes the issue.

[pfalcon]

we should probably change things so TLS is only supported w/Zephyr toolchain.

Right. But that's orthogonal to the missing abort() in minlibc, PR #29542.

[andrewboie]

It's not clear to me the root cause here. Does this toolchain really not support TLS at all? Or is this just some reference to abort() from libgcc that is simply fixed by #29542

[dcpleung]

According to the link from @galak, it looks like the toolchain is built without TLS support (as configured with --disable-tls).