--- a/ncurses/tinfo/read_entry.c
+++ b/ncurses/tinfo/read_entry.c
@@ -98,28 +98,28 @@ convert_32bits(char *buf, NCURSES_INT2 *Numbers, int count)
     }
     return size;
 }
 #else
 static size_t
 convert_32bits(char *buf, NCURSES_INT2 *Numbers, int count)
 {
     int i, j;
     unsigned char ch;
     for (i = 0; i < count; i++) {
-	int value = 0;
+	unsigned value = 0;
 	for (j = 0; j < SIZEOF_32BITS; ++j) {
 	    ch = UChar(*buf++);
-	    value |= (ch << (8 * j));
+	    value |= ((unsigned)ch << (8 * j));
 	}
-	if (value == -1)
+	if (value == ~0u)
 	    Numbers[i] = ABSENT_NUMERIC;
-	else if (value == -2)
+	else if (value == ~0u - 1)
 	    Numbers[i] = CANCELLED_NUMERIC;
 	else if (value > MAX_OF_TYPE(NCURSES_INT2))
 	    Numbers[i] = MAX_OF_TYPE(NCURSES_INT2);
 	else
 	    Numbers[i] = (short) value;
 	TR(TRACE_DATABASE, ("get Numbers[%d]=%d", i, Numbers[i]));
     }
     return SIZEOF_SHORT;
 }