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diff --git a/Build/source/libs/mpfr/mpfr-src/src/atanh.c b/Build/source/libs/mpfr/mpfr-src/src/atanh.c
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--- a/Build/source/libs/mpfr/mpfr-src/src/atanh.c
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-/* mpfr_atanh -- Inverse Hyperbolic Tangente
-
-Copyright 2001-2020 Free Software Foundation, Inc.
-Contributed by the AriC and Caramba 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
-https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
-51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
-
-#define MPFR_NEED_LONGLONG_H
-#include "mpfr-impl.h"
-
-/* Put in y an approximation of atanh(x) for x small.
- We assume x <= 1/2, in which case:
- x <= y ~ atanh(x) = x + x^3/3 + x^5/5 + x^7/7 + ... <= 2*x.
- Return k such that the error is bounded by 2^k*ulp(y).
-*/
-static int
-mpfr_atanh_small (mpfr_ptr y, mpfr_srcptr x)
-{
- mpfr_prec_t p = MPFR_PREC(y), err;
- mpfr_t x2, t, u;
- unsigned long i;
- int k;
-
- MPFR_ASSERTD(MPFR_GET_EXP (x) <= -1);
-
- /* in the following, theta represents a value with |theta| <= 2^(1-p)
- (might be a different value each time) */
-
- mpfr_init2 (t, p);
- mpfr_init2 (u, p);
- mpfr_init2 (x2, p);
- mpfr_set (t, x, MPFR_RNDF); /* t = x * (1 + theta) */
- mpfr_set (y, t, MPFR_RNDF); /* exact */
- mpfr_sqr (x2, x, MPFR_RNDF); /* x2 = x^2 * (1 + theta) */
- for (i = 3; ; i += 2)
- {
- mpfr_mul (t, t, x2, MPFR_RNDF); /* t = x^i * (1 + theta)^i */
- mpfr_div_ui (u, t, i, MPFR_RNDF); /* u = x^i/i * (1 + theta)^(i+1) */
- if (MPFR_GET_EXP (u) <= MPFR_GET_EXP (y) - p) /* |u| < ulp(y) */
- break;
- mpfr_add (y, y, u, MPFR_RNDF); /* error <= ulp(y) */
- }
- /* We assume |(1 + theta)^(i+1)| <= 2.
- The neglected part is at most |u| + |u|/4 + |u|/16 + ... <= 4/3*|u|,
- which has to be multiplied by |(1 + theta)^(i+1)| <= 2, thus at most
- 3 ulp(y).
- The rounding error on y is bounded by:
- * for the (i-3)/2 add/sub, each error is bounded by ulp(y_i),
- where y_i is the current value of y, which is bounded by ulp(y)
- for y the final value (since it increases in absolute value),
- this yields (i-3)/2*ulp(y)
- * from Lemma 3.1 from [Higham02] (see algorithms.tex),
- the relative error on u at step i is bounded by:
- (i+1)*epsilon/(1-(i+1)*epsilon) where epsilon = 2^(1-p).
- If (i+1)*epsilon <= 1/2, then the relative error on u at
- step i is bounded by 2*(i+1)*epsilon, and since |u| <= 1/2^(i+1)
- at step i, this gives an absolute error bound of;
- 2*epsilon*x*(4/2^4 + 6/2^6 + 8/2^8 + ...) = 2*2^(1-p)*x*(7/18) =
- 14/9*2^(-p)*x <= 2*ulp(x).
-
- If (i+1)*epsilon <= 1/2, then the relative error on u at step i
- is bounded by (i+1)*epsilon/(1-(i+1)*epsilon) <= 1, thus it follows
- |(1 + theta)^(i+1)| <= 2.
-
- Finally the total error is bounded by 3*ulp(y) + (i-3)/2*ulp(y) +2*ulp(x).
- Since x <= 2*y, we have ulp(x) <= 2*ulp(y), thus the error is bounded by:
- (i+7)/2*ulp(y).
- */
- err = (i + 8) / 2; /* ceil((i+7)/2) */
- k = __gmpfr_int_ceil_log2 (err);
- MPFR_ASSERTN(k + 2 < p);
- /* if k + 2 < p, since k = ceil(log2(err)), we have err <= 2^k <= 2^(p-3),
- thus i+7 <= 2*err <= 2^(p-2), thus (i+7)*epsilon <= 1/2, which implies
- our assumption (i+1)*epsilon <= 1/2. */
- mpfr_clear (t);
- mpfr_clear (u);
- mpfr_clear (x2);
- return k;
-}
-
-/* The computation of atanh is done by:
- atanh = ln((1+x)/(1-x)) / 2
- except when x is very small, in which case atanh = x + tiny error,
- and when x is small, where we use directly the Taylor expansion.
-*/
-
-int
-mpfr_atanh (mpfr_ptr y, mpfr_srcptr xt, mpfr_rnd_t rnd_mode)
-{
- int inexact;
- mpfr_t x, t, te;
- mpfr_prec_t Nx, Ny, Nt;
- mpfr_exp_t err;
- MPFR_ZIV_DECL (loop);
- MPFR_SAVE_EXPO_DECL (expo);
-
- MPFR_LOG_FUNC
- (("x[%Pu]=%.*Rg rnd=%d", mpfr_get_prec (xt), mpfr_log_prec, xt, rnd_mode),
- ("y[%Pu]=%.*Rg inexact=%d",
- mpfr_get_prec (y), mpfr_log_prec, y, inexact));
-
- /* Special cases */
- if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (xt)))
- {
- /* atanh(NaN) = NaN, and atanh(+/-Inf) = NaN since tanh gives a result
- between -1 and 1 */
- if (MPFR_IS_NAN (xt) || MPFR_IS_INF (xt))
- {
- MPFR_SET_NAN (y);
- MPFR_RET_NAN;
- }
- else /* necessarily xt is 0 */
- {
- MPFR_ASSERTD (MPFR_IS_ZERO (xt));
- MPFR_SET_ZERO (y); /* atanh(0) = 0 */
- MPFR_SET_SAME_SIGN (y,xt);
- MPFR_RET (0);
- }
- }
-
- /* atanh (x) = NaN as soon as |x| > 1, and arctanh(+/-1) = +/-Inf */
- if (MPFR_UNLIKELY (MPFR_GET_EXP (xt) > 0))
- {
- if (MPFR_GET_EXP (xt) == 1 && mpfr_powerof2_raw (xt))
- {
- MPFR_SET_INF (y);
- MPFR_SET_SAME_SIGN (y, xt);
- MPFR_SET_DIVBY0 ();
- MPFR_RET (0);
- }
- MPFR_SET_NAN (y);
- MPFR_RET_NAN;
- }
-
- /* atanh(x) = x + x^3/3 + ... so the error is < 2^(3*EXP(x)-1) */
- MPFR_FAST_COMPUTE_IF_SMALL_INPUT (y, xt, -2 * MPFR_GET_EXP (xt), 1, 1,
- rnd_mode, {});
-
- MPFR_SAVE_EXPO_MARK (expo);
-
- /* Compute initial precision */
- Nx = MPFR_PREC (xt);
- MPFR_TMP_INIT_ABS (x, xt);
- Ny = MPFR_PREC (y);
- Nt = MAX (Nx, Ny);
- Nt = Nt + MPFR_INT_CEIL_LOG2 (Nt) + 4;
-
- /* initialize of intermediary variable */
- mpfr_init2 (t, Nt);
- mpfr_init2 (te, Nt);
-
- MPFR_ZIV_INIT (loop, Nt);
- for (;;)
- {
- int k;
-
- /* small case: assuming the AGM algorithm used by mpfr_log uses
- log2(p) steps for a precision of p bits, we try the special
- variant whenever EXP(x) <= -p/log2(p). */
- k = 1 + __gmpfr_int_ceil_log2 (Ny); /* the +1 avoids a division by 0
- when Ny=1 */
- if (MPFR_GET_EXP (x) <= - 1 - (mpfr_exp_t) (Ny / k))
- /* this implies EXP(x) <= -1 thus x < 1/2 */
- {
- err = Nt - mpfr_atanh_small (t, x);
- goto round;
- }
-
- /* compute atanh */
- mpfr_ui_sub (te, 1, x, MPFR_RNDU); /* (1-x) with x = |xt| */
- mpfr_add_ui (t, x, 1, MPFR_RNDD); /* (1+x) */
- mpfr_div (t, t, te, MPFR_RNDN); /* (1+x)/(1-x) */
- mpfr_log (t, t, MPFR_RNDN); /* ln((1+x)/(1-x)) */
- mpfr_div_2ui (t, t, 1, MPFR_RNDN); /* ln((1+x)/(1-x)) / 2 */
-
- /* error estimate: see algorithms.tex */
- /* FIXME: this does not correspond to the value in algorithms.tex!!! */
- /* err = Nt - __gmpfr_ceil_log2(1+5*pow(2,1-MPFR_EXP(t))); */
- err = Nt - (MAX (4 - MPFR_GET_EXP (t), 0) + 1);
-
- round:
- if (MPFR_LIKELY (MPFR_IS_ZERO (t)
- || MPFR_CAN_ROUND (t, err, Ny, rnd_mode)))
- break;
-
- /* reactualisation of the precision */
- MPFR_ZIV_NEXT (loop, Nt);
- mpfr_set_prec (t, Nt);
- mpfr_set_prec (te, Nt);
- }
- MPFR_ZIV_FREE (loop);
-
- inexact = mpfr_set4 (y, t, rnd_mode, MPFR_SIGN (xt));
-
- mpfr_clear (t);
- mpfr_clear (te);
-
- MPFR_SAVE_EXPO_FREE (expo);
- return mpfr_check_range (y, inexact, rnd_mode);
-}