I'm revamping my testing efforts, building cross compilers based on targets listed in ./contrib/config-list.mk.

With .../configure --target=mcore-elf --enable-werror-always --enable-languages=all --prefix=/tmp/gcc-mcore-elf (using g++ (Debian 20210320-1) 11.0.1 20210320 (experimental) [master revision 3279a9a5a9a:6526c452d22:5f256a70a05fcfc5a1caf56678ceb12b4f87f781] as the host's compiler), build breaks (as of 37846c42f1f5ac4d9ba190d49c4373673c89c8b5) with this (cf. http://toolchain.lug-owl.de:8080/jobs/gcc-mcore-elf/11):

make all-gcc
[...]
all 2021-04-29 09:39:37.528923] /usr/lib/gcc-snapshot/bin/g++  -fno-PIE -c   -g -O2 -DIN_GCC  -DCROSS_DIRECTORY_STRUCTURE   -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wno-error=format-diag -Wmissing-format-attribute -Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -Werror -fno-common  -DHAVE_CONFIG_H -I. -I. -I../.././gcc -I../.././gcc/. -I../.././gcc/../include -I../.././gcc/../libcpp/include -I../.././gcc/../libcody  -I../.././gcc/../libdecnumber -I../.././gcc/../libdecnumber/dpd -I../libdecnumber -I../.././gcc/../libbacktrace   -o dwarf2out.o -MT dwarf2out.o -MMD -MP -MF ./.deps/dwarf2out.TPo ../.././gcc/dwarf2out.c
[all 2021-04-29 09:40:06.839260] ../.././gcc/dwarf2out.c: In function 'void output_one_line_info_table(dw_line_info_table*)':
[all 2021-04-29 09:40:06.839476] ../.././gcc/dwarf2out.c:12831:82: error: 'prev_addr' may be used uninitialized in this function [-Werror=maybe-uninitialized]
[all 2021-04-29 09:40:06.839552] 12831 |             ASM_GENERATE_INTERNAL_LABEL (prev_label, LINE_CODE_LABEL, prev_addr->val);
[all 2021-04-29 09:40:06.839627]       |                                                                                  ^~~
[all 2021-04-29 09:41:39.466117] cc1plus: all warnings being treated as errors
[all 2021-04-29 09:41:39.525930] make[1]: *** [Makefile:1141: dwarf2out.o] Error 1
[all 2021-04-29 09:41:39.578999] make[1]: Leaving directory '/var/lib/laminar/run/gcc-mcore-elf/11/gcc/host-x86_64-pc-linux-gnu/gcc'
[all 2021-04-29 09:41:39.818955] make: *** [Makefile:4428: all-gcc] Error 2


Thanks,
Jan-Benedict