https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87891
--- Comment #5 from Douglas Mencken <dougmencken at gmail dot com> ---
Then when I do
# header search path is -isystem ./include
ln -s /usr/include/sys ./gcc/include/sys
ln -s /usr/include/machine ./gcc/include/machine
ln -s /usr/include/ppc ./gcc/include/ppc
ln -s /usr/include/unistd.h ./gcc/include/unistd.h
ln -s /usr/include/_types.h ./gcc/include/_types.h
it succeeds to the next missing header
enable-execute-stack.c:27:10: fatal error: stdlib.h: No such file or directory
#include <stdlib.h>
^~~~~~~~~~
Why I need to do this by hand?