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+/* mpfr_init2 -- initialize a floating-point number with given precision
+
+Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.
+Contributed by the AriC and Caramel projects, INRIA.
+
+This file is part of the GNU MPFR Library.
+
+The GNU MPFR Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 3 of the License, or (at your
+option) any later version.
+
+The GNU MPFR Library is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
+License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see
+http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
+51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+#include "mpfr-impl.h"
+
+void
+mpfr_init2 (mpfr_ptr x, mpfr_prec_t p)
+{
+ mp_size_t xsize;
+ mpfr_limb_ptr tmp;
+
+ /* Check if we can represent the number of limbs
+ * associated to the maximum of mpfr_prec_t*/
+ MPFR_ASSERTN( MP_SIZE_T_MAX >= (MPFR_PREC_MAX/BYTES_PER_MP_LIMB) );
+
+ /* Check for correct GMP_NUMB_BITS and BYTES_PER_MP_LIMB */
+ MPFR_ASSERTN( GMP_NUMB_BITS == BYTES_PER_MP_LIMB * CHAR_BIT
+ && sizeof(mp_limb_t) == BYTES_PER_MP_LIMB );
+
+ MPFR_ASSERTN (mp_bits_per_limb == GMP_NUMB_BITS);
+
+ /* Check for correct EXP NAN, ZERO & INF in both mpfr.h and mpfr-impl.h */
+ MPFR_ASSERTN( __MPFR_EXP_NAN == MPFR_EXP_NAN );
+ MPFR_ASSERTN( __MPFR_EXP_ZERO == MPFR_EXP_ZERO );
+ MPFR_ASSERTN( __MPFR_EXP_INF == MPFR_EXP_INF );
+
+ MPFR_ASSERTN( MPFR_EMAX_MAX <= (MPFR_EXP_MAX >> 1) );
+ MPFR_ASSERTN( MPFR_EMIN_MIN >= -(MPFR_EXP_MAX >> 1) );
+
+ /* p=1 is not allowed since the rounding to nearest even rule requires at
+ least two bits of mantissa: the neighbours of 3/2 are 1*2^0 and 1*2^1,
+ which both have an odd mantissa */
+ MPFR_ASSERTN(p >= MPFR_PREC_MIN && p <= MPFR_PREC_MAX);
+
+ xsize = MPFR_PREC2LIMBS (p);
+ tmp = (mpfr_limb_ptr) (*__gmp_allocate_func)(MPFR_MALLOC_SIZE(xsize));
+
+ MPFR_PREC(x) = p; /* Set prec */
+ MPFR_EXP (x) = MPFR_EXP_INVALID; /* make sure that the exp field has a
+ valid value in the C point of view */
+ MPFR_SET_POS(x); /* Set a sign */
+ MPFR_SET_MANT_PTR(x, tmp); /* Set Mantissa ptr */
+ MPFR_SET_ALLOC_SIZE(x, xsize); /* Fix alloc size of Mantissa */
+ MPFR_SET_NAN(x); /* initializes to NaN */
+}
+
+#ifdef MPFR_USE_OWN_MPFR_TMP_ALLOC
+static unsigned char mpfr_stack_tab[8000000];
+unsigned char *mpfr_stack = mpfr_stack_tab;
+#endif