From cb8fce4b4fa4557641e8ca4cc7061a7de9e44749 Mon Sep 17 00:00:00 2001 From: nsz Date: Fri, 23 Mar 2012 01:18:12 +0100 Subject: [PATCH] fix tgammal: don't set the signgam global (tgamma must be thread-safe, signgam is for lgamma* functions) --- src/math/tgammal.c | 19 ++++++------------- 1 file changed, 6 insertions(+), 13 deletions(-) diff --git a/src/math/tgammal.c b/src/math/tgammal.c index 1b460da5..86782a96 100644 --- a/src/math/tgammal.c +++ b/src/math/tgammal.c @@ -21,7 +21,6 @@ * SYNOPSIS: * * long double x, y, tgammal(); - * extern int signgam; * * y = tgammal( x ); * @@ -29,10 +28,7 @@ * DESCRIPTION: * * Returns gamma function of the argument. The result is - * correctly signed, and the sign (+1 or -1) is also - * returned in a global (extern) variable named signgam. - * This variable is also filled in by the logarithmic gamma - * function lgamma(). + * correctly signed. * * Arguments |x| <= 13 are reduced by recurrence and the function * approximated by a rational function of degree 7/8 in the @@ -209,9 +205,8 @@ static long double stirf(long double x) long double tgammal(long double x) { long double p, q, z; - int i; + int i, sign; - signgam = 1; if (isnan(x)) return NAN; if (x == INFINITY) @@ -220,6 +215,7 @@ long double tgammal(long double x) return x - x; q = fabsl(x); if (q > 13.0) { + sign = 1; if (q > MAXGAML) goto goverf; if (x < 0.0) { @@ -228,7 +224,7 @@ long double tgammal(long double x) return (x - x) / (x - x); i = p; if ((i & 1) == 0) - signgam = -1; + sign = -1; z = q - p; if (z > 0.5L) { p += 1.0; @@ -238,13 +234,13 @@ long double tgammal(long double x) z = fabsl(z) * stirf(q); if (z <= PIL/LDBL_MAX) { goverf: - return signgam * INFINITY; + return sign * INFINITY; } z = PIL/z; } else { z = stirf(x); } - return signgam * z; + return sign * z; } z = 1.0; @@ -269,8 +265,6 @@ goverf: p = __polevll(x, P, 7); q = __polevll(x, Q, 8); z = z * p / q; - if(z < 0) - signgam = -1; return z; small: @@ -279,7 +273,6 @@ small: if (x < 0.0) { x = -x; q = z / (x * __polevll(x, SN, 8)); - signgam = -1; } else q = z / (x * __polevll(x, S, 8)); return q; -- 2.11.0