diff --git a/cmake/Version.cmake b/cmake/Version.cmake
index 3677e80..490de2c 100644
--- a/cmake/Version.cmake
+++ b/cmake/Version.cmake
@@ -32,7 +32,7 @@ function (write_static_version_header hash)
 endfunction ()
 
 find_package(Git QUIET)
-if ("$Format:$" STREQUAL "")
+if ("$Format:$" STREQUAL "" OR NOT EXISTS .git)
   # We're in a tarball; use hard-coded variables.
   write_static_version_header("release")
 elseif (GIT_FOUND OR Git_FOUND)