cpp: don't handroll an incorrect strtoul(3c), use the one in libc
The previous implementation would parse 0x7ff as 0x755 (etc).

@@ -78,11 +78,11 @@
 #define COFF 128
 #else
 #define COFF 0
 #endif
 
-static  int     tobinary(char *, int);
+static  long    tobinary(char *, int);
 
 int
 yylex(void)
 {
         static int ifdef=0;

@@ -133,33 +133,20 @@
 ret:
         *newp=savc; outp=inp=newp; return(val);
 }
 }
 
-static int
-tobinary(st, b)
-        char    *st;
-        int     b;
+static long
+tobinary(char *st, int b)
 {
-        int n, c, t;
-        char *s;
-        n=0;
-        s=st;
-        while ((c = *s++) != '\0') {
-        switch(c) {
-                case '0': case '1': case '2': case '3': case '4': 
-                case '5': case '6': case '7': case '8': case '9': 
-                        t = c-'0'; break;
-                case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': 
-                        t = c-'a'; if (b>10) break;
-                case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': 
-                        t = c - 'A'; if (b>10) break;
-                default:
-                        t = -1;
-                        if ( c=='l' || c=='L') if (*s=='\0') break;
-                        pperror("Illegal number %s", st);
+        char *tmp;
+        int n;
+        n = strtoul(st, &tmp, b);
+        if (*tmp != '\0') {
+                if ((strcasecmp(tmp, "L") != 0) &&
+                    (strcasecmp(tmp, "LL") != 0) &&
+                    (strcasecmp(tmp, "UL") != 0) &&
+                    (strcasecmp(tmp, "ULL") != 0))
+                        pperror("illegal number: %s", st);
         }
-        if (t<0) break;
-        n = n*b+t;
-        }
-return(n);
+        return(n);
 }