https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92646
--- Comment #2 from Mysaa <samyavrillon at netcourrier dot com> --- I tried again to compile in a dedicated directory, the same error occurs : /home/bernard/building/gcc-9.2.0/bld/./gcc/xgcc -B/home/bernard/building/gcc-9.2.0/bld/./gcc/ -B/usr/local/armv7l-unknown-linux-gnueabihf/bin/ -B/usr/local/armv7l-unknown-linux-gnueabihf/lib/ -isystem /usr/local/armv7l-unknown-linux-gnueabihf/include -isystem /usr/local/armv7l-unknown-linux-gnueabihf/sys-include -fno-checking -g -O2 -O2 -g -O2 -DIN_GCC -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wno-format -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition -isystem ./include -fPIC -fno-inline -g -DIN_LIBGCC2 -fbuilding-libgcc -fno-stack-protector -fPIC -fno-inline -I. -I. -I../.././gcc -I../../../libgcc -I../../../libgcc/. -I../../../libgcc/../gcc -I../../../libgcc/../include -DHAVE_CC_TLS -o _muldi3.o -MT _muldi3.o -MD -MP -MF _muldi3.dep -DL_muldi3 -c ../../../libgcc/libgcc2.c -fvisibility=hidden -DHIDE_EXPORTS In file included from /usr/include/stdio.h:27, from ../../../libgcc/../gcc/tsystem.h:87, from ../../../libgcc/libgcc2.c:27: /usr/include/features.h:364:12: fatal error: sys/cdefs.h: No such file or directory 364 | # include <sys/cdefs.h> | ^~~~~~~~~~~~~ compilation terminated. I am on Armbian, a arm version of debian for OrangepiPC, with a dedicated apt repository.