Develop three extra digits, not just one.

2 files changed, 14 insertions, 5 deletions

diff --git a/ChangeLog b/ChangeLog
index d49bf5298..e6fa8c24d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2000-07-31  Torbjorn Granlund  <tege@swox.com>
+
+	* mpf/get_str.c: Develop three extra digits, not just one.
+
 2000-07-31  Kevin Ryde  <kevin@swox.se>
 
 	* gmp.texi (References): Add URL for invariant division.
@@ -56,7 +60,7 @@
 	New functions.
 	(numberof, TMP_ALLOC_TYPE etc, _MP_ALLOCATE_FUNC_TYPE etc,
 	UNSIGNED_TYPE_MAX etc): New macros.
-	
+
 	* tune/*: Add FFT threshold tuning and speed measuring.
 	* tune/common.c: Avoid huge macro expansions for umul and udiv.
 
@@ -99,7 +103,7 @@
 
 	* configure.in: Add sparc64-*-linux* support (from Jakub Jelinek).
 	* configure: Regenerate.
-	
+
 	* mpn/sparc64/rshift.asm: Use %g5 instead of volatile stack frame area
 	for return value (from Jakub Jelinek).
 	* mpn/sparc64/lshift.asm: Likewise.
diff --git a/mpf/get_str.c b/mpf/get_str.c
index a2c53a35d..a9c6551ce 100644
--- a/mpf/get_str.c
+++ b/mpf/get_str.c
@@ -317,13 +317,18 @@ mpf_get_str (digit_ptr, exp, base, n_digits, u)
       /* fall out to general code... */
     }
 
+  /* Now that we have normalized the number, develop the digits, essentially by
+     multiplying it by BASE.  We initially develop at least 3 extra digits,
+     since the two leading digits might become zero, and we need one extra for
+     rounding the output properly.  */
+
   /* Allocate temporary digit space.  We can't put digits directly in the user
      area, since we generate more digits than requested.  (We allocate
-     BITS_PER_MP_LIMB + 1 extra bytes because of the digit block nature of the
+     BITS_PER_MP_LIMB extra bytes because of the digit block nature of the
      conversion.)  */
-  tstr = (unsigned char *) TMP_ALLOC (n_digits + BITS_PER_MP_LIMB + 1);
+  tstr = (unsigned char *) TMP_ALLOC (n_digits + BITS_PER_MP_LIMB + 3);
 
-  for (digits_computed_so_far = 0; digits_computed_so_far <= n_digits;
+  for (digits_computed_so_far = 0; digits_computed_so_far < n_digits + 3;
        digits_computed_so_far += dig_per_u)
     {
       mp_limb_t cy;