[PATCH v5 2/3] musl: Use __builtin_rint if available.

[Piotr Caban]

From: Piotr Caban

---
 libs/musl/src/math/rint.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libs/musl/src/math/rint.c b/libs/musl/src/math/rint.c
index b9e3cbb0ec2..61df07485b8 100644
--- a/libs/musl/src/math/rint.c
+++ b/libs/musl/src/math/rint.c
@@ -7,6 +7,9 @@ static const float_t toint = 1 / FLT_EPSILON;

double __cdecl rint(double x)
 {
+#if defined(__GNUC__) || defined(__clang__)
+    return __builtin_rint(x);
+#else
     union {double f; uint64_t i;} u = {x};
     int e = (u.i >> 52 & 0x7ff) - 0x3ff;
     int s = u.i>>63;
@@ -49,4 +52,5 @@ double __cdecl rint(double x)
     }

return z;
+#endif
 }