diff --git a/include/utils/Compat.h b/include/utils/Compat.h
index fb7748e..20a6920 100644
--- a/include/utils/Compat.h
+++ b/include/utils/Compat.h
@@ -19,11 +19,9 @@
 
 #include <unistd.h>
 
-/* Compatibility definitions for non-Linux (i.e., BSD-based) hosts. */
-#ifndef HAVE_OFF64_T
-#if _FILE_OFFSET_BITS < 64
-#error "_FILE_OFFSET_BITS < 64; large files are not supported on this platform"
-#endif /* _FILE_OFFSET_BITS < 64 */
+#if defined(__APPLE__)
+
+/* Mac OS has always had a 64-bit off_t, so it doesn't have off64_t. */
 
 typedef off_t off64_t;
 
@@ -31,13 +29,11 @@
     return lseek(fd, offset, whence);
 }
 
-#ifdef HAVE_PREAD
 static inline ssize_t pread64(int fd, void* buf, size_t nbytes, off64_t offset) {
     return pread(fd, buf, nbytes, offset);
 }
-#endif
 
-#endif /* !HAVE_OFF64_T */
+#endif /* __APPLE__ */
 
 #if HAVE_PRINTF_ZD
 #  define ZD "%zd"