Most relevant configure and test flags: --target arm-eabi --disable-multilib --with-mode=thumb --with-cpu=cortex-m33 --with-float=hard --target_board=-mthumb/-march=armv8-m.main+dsp+fp/-mtune=cortex-m33/-mfloat-abi=hard/-mfpu=auto qemu-cpu=cortex-m33

Full configure and make flags for each step:

# 04-build_abe-binutils
(cd /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master && /bin/bash /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/snapshots/binutils.git~master/configure SHELL=/bin/bash  --enable-lto --enable-plugins --enable-gold --disable-werror CPPFLAGS=-UFORTIFY_SOURCE --with-pkgversion=Linaro_Binutils-2025.12.04 --disable-gdb --disable-gdbserver --disable-sim --disable-libdecnumber --disable-readline --with-sysroot=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu/arm-eabi --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --target=arm-eabi --prefix=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu)
make SHELL=/bin/bash -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master  -j 32 LDFLAGS_FOR_TARGET=" --specs=rdimon.specs"  CFLAGS_FOR_BUILD="-pipe -g -O2" CXXFLAGS_FOR_BUILD="-pipe -g -O2" LDFLAGS_FOR_BUILD="-static-libgcc" 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/make-binutils.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/bfd diststuff install-man 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/make-binutils.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/binutils diststuff install-man 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/make-binutils.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/gas diststuff install-man 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/make-binutils.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/gold diststuff install-man 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/make-binutils.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/gprof diststuff install-man 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/make-binutils.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/ld diststuff install-man 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/make-binutils.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master install-html install-info 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/make-binutils.log
make install  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/binutils-binutils.git~master/make-binutils.log

# 05-build_abe-stage1
(cd /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage1 && /bin/bash /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/snapshots/gcc.git~master/configure SHELL=/bin/bash  --with-mpc=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu --with-mpfr=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu --with-gmp=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu --with-gnu-as --with-gnu-ld --disable-libmudflap --enable-lto --enable-shared --without-included-gettext --enable-nls --with-system-zlib --disable-sjlj-exceptions --enable-gnu-unique-object --enable-linker-build-id --disable-libstdcxx-pch --enable-c99 --enable-clocale=gnu --enable-libstdcxx-debug --enable-long-long --with-cloog=no --with-ppl=no --with-isl=no --enable-threads=no --disable-multiarch --disable-multilib --with-mode=thumb --with-cpu=cortex-m33 --with-float=hard --disable-libssp --disable-libquadmath --disable-threads --without-headers --with-newlib --disable-libmudflap --disable-decimal-float --disable-libgomp --disable-libatomic --disable-libsanitizer --disable-plugins --disable-libitm --disable-libvtv --disable-shared --enable-languages=c,c++ --disable-libstdcxx --disable-bootstrap --prefix=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu  --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --target=arm-eabi)
make SHELL=/bin/bash -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage1  -j 32 LDFLAGS_FOR_TARGET=" --specs=rdimon.specs"  CFLAGS_FOR_BUILD="-pipe -g -O2" CXXFLAGS_FOR_BUILD="-pipe -g -O2" LDFLAGS_FOR_BUILD="-static-libgcc" MAKEINFOFLAGS=--force 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage1/make-gcc-stage1.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage1/gcc install-man 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage1/make-gcc-stage1.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage1 install-html install-info 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage1/make-gcc-stage1.log
make install  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage1 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage1/make-gcc-stage1.log

# 07-build_abe-newlib
(cd /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/newlib-newlib.git~master && /bin/bash /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/snapshots/newlib.git~master/configure SHELL=/bin/bash  --with-newlib --enable-newlib-io-pos-args --enable-newlib-io-c99-formats --enable-newlib-register-fini --enable-newlib-io-long-long --enable-newlib-io-long-double --enable-newlib-mb --disable-newlib-supplied-syscalls --disable-nls --enable-newlib-multithread --enable-newlib-retargetable-locking --enable-newlib-reent-check-verify --host=x86_64-pc-linux-gnu --target=arm-eabi --prefix=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu)
make SHELL=/bin/bash -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/newlib-newlib.git~master  -j 32 LDFLAGS_FOR_TARGET=" --specs=rdimon.specs"  CFLAGS_FOR_BUILD="-pipe -g -O2" CXXFLAGS_FOR_BUILD="-pipe -g -O2" LDFLAGS_FOR_BUILD="-static-libgcc" 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/newlib-newlib.git~master/make-newlib.log
make install  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/newlib-newlib.git~master 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/newlib-newlib.git~master/make-newlib.log

# 08-build_abe-stage2
(cd /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage2 && /bin/bash /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/snapshots/gcc.git~master/configure SHELL=/bin/bash  --with-mpc=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu --with-mpfr=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu --with-gmp=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu --with-gnu-as --with-gnu-ld --disable-libmudflap --enable-lto --enable-shared --without-included-gettext --enable-nls --with-system-zlib --disable-sjlj-exceptions --enable-gnu-unique-object --enable-linker-build-id --disable-libstdcxx-pch --enable-c99 --enable-clocale=gnu --enable-libstdcxx-debug --enable-long-long --with-cloog=no --with-ppl=no --with-isl=no --enable-threads=no --disable-multiarch --disable-multilib --with-mode=thumb --with-cpu=cortex-m33 --with-float=hard --with-sysroot=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu/arm-eabi --with-headers=yes --with-native-system-header-dir=/include --with-newlib --enable-checking=yes --disable-bootstrap --enable-languages=c,c++,lto --prefix=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu  --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --target=arm-eabi)
make SHELL=/bin/bash -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage2  -j 32 LDFLAGS_FOR_TARGET=" --specs=rdimon.specs"  CFLAGS_FOR_BUILD="-pipe -g -O2" CXXFLAGS_FOR_BUILD="-pipe -g -O2" LDFLAGS_FOR_BUILD="-static-libgcc" MAKEINFOFLAGS=--force 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage2/make-gcc-stage2.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage2/gcc install-man 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage2/make-gcc-stage2.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage2/arm-eabi/libstdc++-v3 install-man 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage2/make-gcc-stage2.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage2 install-html install-info 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage2/make-gcc-stage2.log
make install  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage2 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gcc-gcc.git~master-stage2/make-gcc-stage2.log

# 09-build_abe-gdb
(cd /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gdb-gdb.git~master && /bin/bash /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/snapshots/gdb.git~master/configure SHELL=/bin/bash  --with-gnu-ld --enable-plugins --enable-tui --with-pkgversion=Linaro_GDB-2025.12.04 --disable-gas --disable-binutils --disable-elfcpp --disable-ld --disable-gold --disable-gprof --with-python=python3 --disable-werror --with-auto-load-safe-path=\$debugdir:\$datadir/auto-load:/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu/arm-eabi --with-additional-debug-dirs=/usr/lib/debug --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --target=arm-eabi --prefix=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/destdir/x86_64-pc-linux-gnu)
make SHELL=/bin/bash -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gdb-gdb.git~master  -j 32 LDFLAGS_FOR_TARGET=" --specs=rdimon.specs"  CFLAGS_FOR_BUILD="-pipe -g -O2" CXXFLAGS_FOR_BUILD="-pipe -g -O2" LDFLAGS_FOR_BUILD="-static-libgcc" all-gdb 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gdb-gdb.git~master/make-gdb.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gdb-gdb.git~master/gdb diststuff install-html install-info 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gdb-gdb.git~master/make-gdb.log
make SHELL=/bin/bash  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gdb-gdb.git~master/gdb/doc install-man 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gdb-gdb.git~master/make-gdb.log
make install-gdb  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gdb-gdb.git~master 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/gdb-gdb.git~master/make-gdb.log

# 10-build_abe-qemu
(cd /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/qemu-qemu.git~master && /bin/bash /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/snapshots/qemu.git~master/configure   --target-list=arm-linux-user,arm-softmmu --prefix=/home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/hosttools/x86_64-pc-linux-gnu)
make SHELL=/bin/bash -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/qemu-qemu.git~master  -j 32 LDFLAGS_FOR_TARGET=" --specs=rdimon.specs"  CFLAGS_FOR_BUILD="-pipe -g -O2" CXXFLAGS_FOR_BUILD="-pipe -g -O2" LDFLAGS_FOR_BUILD="-static-libgcc" 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/qemu-qemu.git~master/make-qemu.log
make install  -w -C /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/qemu-qemu.git~master 2>&1 | tee -a /home/tcwg-buildslave/workspace/tcwg_gnu_1/abe/builds/x86_64-pc-linux-gnu/arm-eabi/qemu-qemu.git~master/make-qemu.log