Index: Source/util.cpp
===================================================================
--- Source/util.cpp	(revision 7449)
+++ Source/util.cpp	(working copy)
@@ -705,7 +705,7 @@
 {
   UINT64 result = invalid_file_size64;
   // 32bit platforms require _FILE_OFFSET_BITS = 64 to correctly return the size
-#if _XOPEN_SOURCE >= 500 || _POSIX_C_SOURCE >= 200112L
+#if _XOPEN_SOURCE >= 500 || _POSIX_C_SOURCE >= 200112L || defined(__APPLE__) || defined(__FreeBSD__)
   struct stat st;
   if (0 == fstat(fileno(f), &st) && st.st_size <= (sizeof(st.st_size) >= 8 ? (off_t)0x7fffffffffffffffLL : LONG_MAX))
     result = (UINT64) st.st_size;
@@ -741,7 +741,7 @@
 {
 #ifdef _WIN32
   return ~(UINT64)0;
-#elif _XOPEN_SOURCE >= 500 || _POSIX_C_SOURCE >= 200112L
+#elif _XOPEN_SOURCE >= 500 || _POSIX_C_SOURCE >= 200112L || defined(__APPLE__) || defined(__FreeBSD__)
   struct stat st;
   if (sizeof(st.st_size) >= 8)
   {