Make 1984/decot compile under linux

This will not compile with clang which is actually what gcc is under
macOS. Unfortunately clang does not support -traditional-cpp which this
entry requires for modern systems.

We would like to thank Yusuke Endoh for the patch to get this to compile
with gcc. Thank you very much Yusuke!

1984/decot/decot.c

@@ -3,7 +3,6 @@
 #define char k['a']
 #define union static struct
 
-extern int floor;
 double (x1, y1) b,
 char x {sizeof(
     double(%s,%D)(*)())
@@ -24,7 +23,7 @@ _O: while (!(char <<x - dup)) {	/*/*\*/
 
 while(b x 3, i); {
 char x b,i;
-  _0:if(b&&k+
+  _0:if(b&&(int)k+
   sin(signal)		/ *    ((main) (b)-> xO));/*}
   ;
 }