bison-1.00 from 1988 recompiled and changed such that it compiles with gcc-8.3 in 2021 see the file dsmake.output

just type 'make' and a bison1 executable is compiled.
path for the skeletons given to file.c is fixed to
this dir to prevent conflicts with newer bison installed.
'make install' is intentionally turned off, see makefile.

bison -d option generates a .tab.h output file
bison -v option generates a calc.output file
bison -y option generates y.tab.c and y.tab.h like yacc does
bison -o outputfile generated output to another file

test to run calc.y:
./bison1 calc.y
gcc calc.tab.c
./a.out
3+3
6
ctrl-d
