lround() missing in MSVC

lround() is missing in MS Visual-C's <math.h>. Not available anywhere.
Here is an easy patch.

diff --git a/changes/msvc_lround b/changes/msvc_lround
new file mode 100644 (file)
index 0000000..e4aea95
--- /dev/null
+++ b/changes/msvc_lround
@@ -0,0 +1,4 @@
+  o Build fixes:
+    - Provide a substitute implementation of lround() for MSVC, which
+      apparently lacks it.  Patch from Gisle Vanem.
+      

diff --git a/src/common/util.c b/src/common/util.c
index b47b9c5fa28bf9da5b25a7ddeeafa73b7a5a65fa..ee0acbbb07314af44fbe509c9c590ed239b1944d 100644 (file)
--- a/src/common/util.c
+++ b/src/common/util.c
@@ -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. */