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-rw-r--r--src/math/nearbyint.c23
1 files changed, 11 insertions, 12 deletions
diff --git a/src/math/nearbyint.c b/src/math/nearbyint.c
index 714c55ca..7a4c58cf 100644
--- a/src/math/nearbyint.c
+++ b/src/math/nearbyint.c
@@ -1,20 +1,19 @@
#include <fenv.h>
#include <math.h>
-/*
-rint may raise inexact (and it should not alter the fenv otherwise)
-nearbyint must not raise inexact
+/* nearbyint is the same as rint, but it must not raise the inexact exception */
-(according to ieee754r section 7.9 both functions should raise invalid
-when the input is signaling nan, but c99 does not define snan so saving
-and restoring the entire fenv should be fine)
-*/
+double nearbyint(double x)
+{
+#ifdef FE_INEXACT
+ int e;
-double nearbyint(double x) {
- fenv_t e;
-
- fegetenv(&e);
+ e = fetestexcept(FE_INEXACT);
+#endif
x = rint(x);
- fesetenv(&e);
+#ifdef FE_INEXACT
+ if (!e)
+ feclearexcept(FE_INEXACT);
+#endif
return x;
}