Should use strcmp/strncmp instead of memcmp on arm. about dtc HOT 5 CLOSED

Um.. a memcmp() implementation which has alignment constraints is utterly broken. I can't believe that's the case on all ARM systems - what specific environment are you using?

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compiler: gcc-arm-8.2-2018.08-x86_64-aarch64-elf which uses newlib
device: Raspberry Pi 3 B

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S:\src\pios>gcc-arm-8.2-2018.08-i686-mingw32-aarch64-elf\bin\aarch64-elf-gcc -v
Using built-in specs.
COLLECT_GCC=gcc-arm-8.2-2018.08-i686-mingw32-aarch64-elf\bin\aarch64-elf-gcc
COLLECT_LTO_WRAPPER=s:/src/pios/gcc-arm-8.2-2018.08-i686-mingw32-aarch64-elf/bin/../libexec/gcc/aarch64-elf/8.2.1/lto-wrapper.exe
Target: aarch64-elf
Configured with: /tmp/dgboter/bbs/dsggnu-vm-1-x86_64--mingw32-i686/buildbot/mingw32-i686--aarch64-elf/build/src/gcc/configure --target=aarch64-elf --prefix=/tmp/dgboter/bbs/dsggnu-vm-1-x86_64--mingw32-i686/buildbot/mingw32-i686--aarch64-elf/build/build-mingw-aarch64-elf/install// --with-gmp=/tmp/dgboter/bbs/dsggnu-vm-1-x86_64--mingw32-i686/buildbot/mingw32-i686--aarch64-elf/build/build-mingw-aarch64-elf/host-tools --with-mpfr=/tmp/dgboter/bbs/dsggnu-vm-1-x86_64--mingw32-i686/buildbot/mingw32-i686--aarch64-elf/build/build-mingw-aarch64-elf/host-tools --with-mpc=/tmp/dgboter/bbs/dsggnu-vm-1-x86_64--mingw32-i686/buildbot/mingw32-i686--aarch64-elf/build/build-mingw-aarch64-elf/host-tools --with-isl=/tmp/dgboter/bbs/dsggnu-vm-1-x86_64--mingw32-i686/buildbot/mingw32-i686--aarch64-elf/build/build-mingw-aarch64-elf/host-tools --with-pkgversion='GNU Toolchain for the A-profile Architecture 8.2-2018-08 (arm-rel-8.23)' --disable-shared --disable-nls --disable-threads --disable-tls --enable-checking=release --enable-languages=c,c++,fortran --with-newlib --with-libiconv-prefix=/tmp/dgboter/bbs/dsggnu-vm-1-x86_64--mingw32-i686/buildbot/mingw32-i686--aarch64-elf/build/build-mingw-aarch64-elf/host-tools --host=i686-w64-mingw32
Thread model: single
gcc version 8.2.1 20180802 (GNU Toolchain for the A-profile Architecture 8.2-2018-08 (arm-rel-8.23))

from dtc.

Ok, it sounds like that newlib version may be broken for ARM. I'm 99% certain that a memcmp() which doesn't work on unaligned addresses is a serious spec violation.

from dtc.

Checked with some people who know C specs better than I do. A memcmp() that doesn't handle non-aligned addresses is definitely broken. You'll either need to get the bug fixed in your library, or you'll need to supply a working memcmp() via a custom libfdt_env.h.

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