lround() is missing in MS Visual-C's <math.h>. Not available anywhere. Here is an easy patch.
@@ -0,0 +1,4 @@
+ o Build fixes:
+ - Provide a substitute implementation of lround() for MSVC, which
+ apparently lacks it. Patch from Gisle Vanem.
+
@@ -334,7 +334,11 @@ tor_mathlog(double d)
long
tor_lround(double d)
{
+#ifdef _MSC_VER
+ return (long)(d > 0 ? d + 0.5 : ceil(d - 0.5));
+#else
return lround(d);
+#endif
}
/** Returns floor(log2(u64)). If u64 is 0, (incorrectly) returns 0. */