stage0: gcc: In function `uw_frame_state_for': ./unwind-dw2.c:1032: error: dereferencing pointer to incomplete type

[aep]

gcc --version
gcc (GCC) 7.2.0
./build-stage0

_GCC    -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition  -isystem ./include  -fPIC -g -DHAVE_GTHR_DEFAULT -DIN_LIBGCC2 -D__GCC_FLOAT_NOT_NEEDED   -r -nostdinc -nostdlib -o libgcc/./_udiv_w_sdiv.oS libgcc/./_udiv_w_sdiv.o -xassembler -
/tmp/sabotage/src/build/gcc3/gcc-3.4.6/gcc/xgcc -B/tmp/sabotage/src/build/gcc3/gcc-3.4.6/gcc/ -B/x86_64-unknown-linux-gnu/bin/ -B/x86_64-unknown-linux-gnu/lib/ -isystem /x86_64-unknown-linux-gnu/include -isystem /x86_64-unknown-linux-gnu/sys-include -O2  -DIN_GCC    -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition  -isystem ./include  -fPIC -g -DHAVE_GTHR_DEFAULT -DIN_LIBGCC2 -D__GCC_FLOAT_NOT_NEEDED  -I. -I. -I. -I./. -I./../include   -DL_udivmoddi4 -c ./libgcc2.c -fexceptions -fnon-call-exceptions -o libgcc/./_udivmoddi4.o
( nm -pg libgcc/./_udivmoddi4.o | gawk 'NF == 3 && $2 !~ /^[UN]$/ { print "\t.hidden", $3 }'; cat libgcc//stacknote.s ) | /tmp/sabotage/src/build/gcc3/gcc-3.4.6/gcc/xgcc -B/tmp/sabotage/src/build/gcc3/gcc-3.4.6/gcc/ -B/x86_64-unknown-linux-gnu/bin/ -B/x86_64-unknown-linux-gnu/lib/ -isystem /x86_64-unknown-linux-gnu/include -isystem /x86_64-unknown-linux-gnu/sys-include -O2  -DIN_GCC    -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition  -isystem ./include  -fPIC -g -DHAVE_GTHR_DEFAULT -DIN_LIBGCC2 -D__GCC_FLOAT_NOT_NEEDED   -r -nostdinc -nostdlib -o libgcc/./_udivmoddi4.oS libgcc/./_udivmoddi4.o -xassembler -
/tmp/sabotage/src/build/gcc3/gcc-3.4.6/gcc/xgcc -B/tmp/sabotage/src/build/gcc3/gcc-3.4.6/gcc/ -B/x86_64-unknown-linux-gnu/bin/ -B/x86_64-unknown-linux-gnu/lib/ -isystem /x86_64-unknown-linux-gnu/include -isystem /x86_64-unknown-linux-gnu/sys-include -O2  -DIN_GCC    -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition  -isystem ./include  -fPIC -g -DHAVE_GTHR_DEFAULT -DIN_LIBGCC2 -D__GCC_FLOAT_NOT_NEEDED  -I. -I. -I. -I./. -I./../include  -fexceptions -c ./unwind-dw2.c -o libgcc/./unwind-dw2.o
./unwind-dw2.c: In function `uw_frame_state_for':
./unwind-dw2.c:1032: error: dereferencing pointer to incomplete type
make[2]: *** [libgcc.mk:122: libgcc/./unwind-dw2.o] Error 1
make[2]: Leaving directory '/tmp/sabotage/src/build/gcc3/gcc-3.4.6/gcc'
make[1]: *** [Makefile:1261: stmp-multilib] Error 2
make[1]: Leaving directory '/tmp/sabotage/src/build/gcc3/gcc-3.4.6/gcc'
make: *** [Makefile:23374: all-gcc] Error 2

[aep]

FWIW this worked for me https://github.com/JillTyrell/sabotage/commit/e0c93a4d5c36df41049451905d0c36948367e34c