Special case 0.0. Don't call mpn_rshift with 0 count.

Allocate correct amount of memory for numerator.  Delete spurious
ASSERT_ALWAYS(1).

1 files changed, 18 insertions, 10 deletions

diff --git a/mpq/set_d.c b/mpq/set_d.c
index 1f38ac746..37c6452c5 100644
--- a/mpq/set_d.c
+++ b/mpq/set_d.c
@@ -57,6 +57,14 @@ mpq_set_d (dest, d)
   if (exp <= 1)
 #endif
     {
+      if (d == 0.0)
+	{
+	  SIZ(&(dest->_mp_num)) = 0;
+	  SIZ(&(dest->_mp_den)) = 1;
+	  PTR(&(dest->_mp_den))[0] = 1;
+	  return;
+	}
+
       dn = -exp;
       if (dest->_mp_num._mp_alloc < 3)
 	_mpz_realloc (&(dest->_mp_num), 3);
@@ -75,23 +83,27 @@ mpq_set_d (dest, d)
 	np[1] = tp[1], np[0] = tp[0], nn = 2;
 #endif
       dn += nn + 1;
-      ASSERT_ALWAYS (dn > 0);
       if (dest->_mp_den._mp_alloc < dn)
 	_mpz_realloc (&(dest->_mp_den), dn);
       dp = PTR(&(dest->_mp_den));
       MPN_ZERO (dp, dn - 1);
       dp[dn - 1] = 1;
+      count_trailing_zeros (c, np[0] | dp[0]);
+      if (c != 0)
+	{
+	  mpn_rshift (np, np, nn, c);
+	  nn -= np[nn - 1] == 0;
+	  mpn_rshift (dp, dp, dn, c);
+	  dn -= dp[dn - 1] == 0;
+	}
       SIZ(&(dest->_mp_den)) = dn;
       SIZ(&(dest->_mp_num)) = negative ? -nn : nn;
-      count_trailing_zeros (c, np[0] | dp[0]);
-      mpn_rshift (np, np, nn, c);
-      mpn_rshift (dp, dp, dn, c);
     }
   else
     {
       nn = exp;
-      if (dest->_mp_num._mp_alloc < 3)
-	_mpz_realloc (&(dest->_mp_num), 3);
+      if (dest->_mp_num._mp_alloc < nn)
+	_mpz_realloc (&(dest->_mp_num), nn);
       np = PTR(&(dest->_mp_num));
 #if BITS_PER_MP_LIMB == 32
       switch (nn)
@@ -106,8 +118,6 @@ mpq_set_d (dest, d)
 	case 2:
 	  np[1] = tp[2], np[0] = tp[1];
 	  break;
-	case 1:
-	  ASSERT_ALWAYS (1);
 	}
 #else
       switch (nn)
@@ -119,8 +129,6 @@ mpq_set_d (dest, d)
 	case 2:
 	  np[1] = tp[1], np[0] = tp[0];
 	  break;
-	case 1:
-	  ASSERT_ALWAYS (1);
 	}
 #endif
       dp = PTR(&(dest->_mp_den));