[gcalctool] Increase accuracy of internal calculations, don't crash printing numbers when they get too large

[Robert Ancell <rancell src gnome org>]

commit 267eef2f08067ca78ef5042600c049f808b49ad2
Author: Robert Ancell <robert ancell canonical com>
Date:   Mon Aug 30 09:20:24 2010 +1000

    Increase accuracy of internal calculations, don't crash printing numbers when they get too large

 NEWS              |    5 +++++
 src/mp-convert.c  |    5 +++--
 src/mp-internal.h |    2 +-
 3 files changed, 9 insertions(+), 3 deletions(-)
---
diff --git a/NEWS b/NEWS
index 3087d9b..09146cf 100644
--- a/NEWS
+++ b/NEWS
@@ -3,6 +3,11 @@
  *  Copyright (c) 1987-2009 Sun Microsystems, Inc.
  *  All Rights Reserved.
  */
+
+Overview of changes in gcalctool 5.31.91
+
+    * Increase accuracy of internal calculations, don't crash printing numbers
+      when they get too large.
  
 Overview of changes in gcalctool 5.31.90
 
diff --git a/src/mp-convert.c b/src/mp-convert.c
index 8964a77..59d238a 100644
--- a/src/mp-convert.c
+++ b/src/mp-convert.c
@@ -534,15 +534,16 @@ mp_cast_to_string_real(const MPNumber *x, int default_base, int base, int accura
     mp_set_from_mp(&integer_component, &temp);
     do {
         MPNumber t, t2, t3;
+        int64_t d;
 
         mp_divide_integer(&temp, base, &t);
         mp_floor(&t, &t);
         mp_multiply_integer(&t, base, &t2);
 
         mp_subtract(&temp, &t2, &t3);
-        mp_floor(&t3, &t3);
 
-        g_string_prepend_c(string, digits[mp_cast_to_int(&t3)]);
+        d = mp_cast_to_int(&t3);
+        g_string_prepend_c(string, d < 16 ? digits[d] : '?');
 
         mp_set_from_mp(&t, &temp);
     } while (!mp_is_zero(&temp));
diff --git a/src/mp-internal.h b/src/mp-internal.h
index 78d1b31..94b1530 100644
--- a/src/mp-internal.h
+++ b/src/mp-internal.h
@@ -36,7 +36,7 @@
 //    mperr("MP_SIZE TOO SMALL IN CALL TO MPSET, INCREASE MP_SIZE AND DIMENSIONS OF MP ARRAYS TO AT LEAST %d ***", MP.t);
 //    MP.t = MP_SIZE;
 //}
-#define MP_T 55
+#define MP_T 100
 
 void mperr(const char *format, ...) __attribute__((format(printf, 1, 2)));
 void mp_gcd(int64_t *, int64_t *);