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bpo-36106: Resolve sinpi name clash with libm (IEEE-754 violation). (GH-12027) 

The standard math library (libm) may follow IEEE-754 recommendation to
include an implementation of sinPi(), i.e. sinPi(x):=sin(pi*x).
And this triggers a name clash, found by FreeBSD developer
Steve Kargl, who worken on putting sinpi into libm used on FreeBSD
(it has to be named "sinpi", not "sinPi", cf. e.g.
https://en.cppreference.com/w/c/experimental/fpext4).
This commit is contained in:
Dima Pasechnik 2019-02-26 06:36:11 +00:00 committed by Serhiy Storchaka
parent ff3d39faa8
commit f57cd8288d
2 changed files with 5 additions and 4 deletions
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1
Misc/NEWS.d/next/Library/2019-02-25-13-21-43.bpo-36106.VuhEiQ.rst Normal file
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@ -0,0 +1 @@
Resolve potential name clash with libm's sinpi(). Patch by Dmitrii Pasechnik.

8
Modules/mathmodule.c
View File

@ -100,7 +100,7 @@ static const double sqrtpi = 1.772453850905516027298167483341145182798;
}
static double
sinpi(double x)
m_sinpi(double x)
{
double y, r;
int n;
@ -328,7 +328,7 @@ m_tgamma(double x)
integer. */
if (absx > 200.0) {
if (x < 0.0) {
return 0.0/sinpi(x);
return 0.0/m_sinpi(x);
}
else {
errno = ERANGE;
@ -352,7 +352,7 @@ m_tgamma(double x)
}
z = z * lanczos_g / y;
if (x < 0.0) {
r = -pi / sinpi(absx) / absx * exp(y) / lanczos_sum(absx);
r = -pi / m_sinpi(absx) / absx * exp(y) / lanczos_sum(absx);
r -= z * r;
if (absx < 140.0) {
r /= pow(y, absx - 0.5);
@ -423,7 +423,7 @@ m_lgamma(double x)
r += (absx - 0.5) * (log(absx + lanczos_g - 0.5) - 1);
if (x < 0.0)
/* Use reflection formula to get value for negative x. */
r = logpi - log(fabs(sinpi(absx))) - log(absx) - r;
r = logpi - log(fabs(m_sinpi(absx))) - log(absx) - r;
if (Py_IS_INFINITY(r))
errno = ERANGE;
return r;