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).
diff --git a/Modules/mathmodule.c b/Modules/mathmodule.c
index 2272f62..fd0eb32 100644
--- a/Modules/mathmodule.c
+++ b/Modules/mathmodule.c
@@ -100,7 +100,7 @@
}
static double
-sinpi(double x)
+m_sinpi(double x)
{
double y, r;
int n;
@@ -328,7 +328,7 @@
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 @@
}
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 @@
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;