5 files changed, 22 insertions, 9 deletions

diff --git a/init.c b/init.c
index 7f32a64b0..06f814aae 100644
--- a/init.c
+++ b/init.c
@@ -48,6 +48,7 @@ mpfr_init2 (x, p)
     exit (1);
   }
   MPFR_SIZE(x) = xsize;
+  MPFR_CLEAR_FLAGS(x); 
   MPFR_SET_ZERO(x); /* initializes to zero */
   MPFR_EXP(x) = 0; /* avoids uninitialized memory reads for zero */
 }
diff --git a/log.c b/log.c
index 4238b4048..024de8cce 100644
--- a/log.c
+++ b/log.c
@@ -64,16 +64,22 @@ mpfr_log(r, a, rnd_mode)
 
   /* If a is NaN, the result is NaN */
   if (MPFR_IS_NAN(a))
-    { MPFR_SET_NAN(r); return 1; }
+    { MPFR_CLEAR_FLAGS(r); MPFR_SET_NAN(r); return 1; }
   
   if (MPFR_IS_ZERO(a)) 
     {
-      MPFR_SET_INF(r); if (MPFR_SIGN(r) != -1) { MPFR_CHANGE_SIGN(r); }
+      MPFR_CLEAR_FLAGS(r);
+      MPFR_SET_INF(r); 
+      if (MPFR_SIGN(r) != -1) { MPFR_CHANGE_SIGN(r); }
+      return 1; 
     }
 
   if (MPFR_IS_INF(a))
     {
-      MPFR_SET_INF(r); if (MPFR_SIGN(r) != 1) { MPFR_CHANGE_SIGN(r); }
+      MPFR_CLEAR_FLAGS(r);
+      MPFR_SET_INF(r); 
+      if (MPFR_SIGN(r) != 1) { MPFR_CHANGE_SIGN(r); }
+      return 1; 
     }
 
   /* Now we can clear the flags without damage even if r == a */
diff --git a/mpfr.h b/mpfr.h
index 796780c50..b0229936d 100644
--- a/mpfr.h
+++ b/mpfr.h
@@ -105,7 +105,7 @@ typedef union ieee_double_extract Ieee_double_extract;
    bit 30 of _mp_size is used for Nan flag,
    bit 29 of _mp_size is used for Inf flag,
    remaining bits are used to store the number of allocated limbs */
-#define MPFR_CLEAR_FLAGS(x) (((x) -> _mp_size &= ~(0x70000000)))
+#define MPFR_CLEAR_FLAGS(x) (((x) -> _mp_size &= ~(3 << 29)))
 #define MPFR_IS_NAN(x) (((x)->_mp_size >> 30)&1)
 #define MPFR_SET_NAN(x) ((x)->_mp_size |= (1<<30))
 #define MPFR_IS_INF(x) (((x)->_mp_size >> 29)&1)
diff --git a/mul.c b/mul.c
index bf89576c5..4de579cae 100644
--- a/mul.c
+++ b/mul.c
@@ -46,26 +46,30 @@ mpfr_mul(a, b, c, rnd_mode)
   TMP_DECL(marker); 
 
   /* deal with NaN and zero */
-  if (MPFR_IS_NAN(b) || MPFR_IS_NAN(c)) { MPFR_SET_NAN(a); return; }
+  if (MPFR_IS_NAN(b) || MPFR_IS_NAN(c)) 
+    { MPFR_CLEAR_FLAGS(a); MPFR_SET_NAN(a); return; }
   if (MPFR_IS_INF(b)) 
     {
-      if (!MPFR_NOTZERO(c)) { MPFR_SET_NAN(a); return; }
+      if (!MPFR_NOTZERO(c)) { MPFR_CLEAR_FLAGS(a); MPFR_SET_NAN(a); return; }
       else 
 	{ 
 	  if (MPFR_SIGN(a) != MPFR_SIGN(b) * MPFR_SIGN(c)) MPFR_CHANGE_SIGN(a);
+	  MPFR_CLEAR_FLAGS(a); 
 	  MPFR_SET_INF(a); return; 
 	}
     }
   else if (MPFR_IS_INF(c)) 
     {
-      if (!MPFR_NOTZERO(b)) { MPFR_SET_NAN(a); return; }
+      if (!MPFR_NOTZERO(b)) { MPFR_CLEAR_FLAGS(a); MPFR_SET_NAN(a); return; }
       else 
 	{ 
 	  if (MPFR_SIGN(a) != MPFR_SIGN(b) * MPFR_SIGN(c)) MPFR_CHANGE_SIGN(a);
-	  MPFR_SET_INF(a); return; 
+	  MPFR_CLEAR_FLAGS(a); MPFR_SET_INF(a); return; 
 	}
     }
-  if (!MPFR_NOTZERO(b) || !MPFR_NOTZERO(c)) { MPFR_SET_ZERO(a); return; }
+
+  if (!MPFR_NOTZERO(b) || !MPFR_NOTZERO(c)) 
+    { MPFR_CLEAR_FLAGS(a); MPFR_SET_ZERO(a); return; }
 
   sign_product = MPFR_SIGN(b) * MPFR_SIGN(c);
 
diff --git a/pow.c b/pow.c
index df76a4689..ab84106f8 100644
--- a/pow.c
+++ b/pow.c
@@ -41,12 +41,14 @@ mpfr_pow_ui (x, y, n, rnd)
 
   if (MPFR_IS_INF(y)) 
     {
+      MPFR_CLEAR_FLAGS(x); 
       if (n == 0) { MPFR_SET_NAN(x); return 0; }
       else if ((MPFR_SIGN(y) < 0 && (MPFR_SIGN(x) > 0 || n % 2 == 0)) ||
 	       (MPFR_SIGN(y) > 0 && (MPFR_SIGN(x) < 0 && n % 2 == 1)))
 	MPFR_CHANGE_SIGN(x); 
       MPFR_SET_INF(x); return 0; 
     }
+  if (MPFR_IS_NAN(y)) { MPFR_CLEAR_FLAGS(x); MPFR_SET_NAN(x); return 0; }
 
   MPFR_CLEAR_FLAGS(x); 
   if (n==0) { mpfr_set_ui(x, 1, rnd); return 0; }