diff --git a/autogen.sh b/autogen.sh
index 7d5ffd856..6b08f3cd5 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -13,7 +13,7 @@ if test -d .git; then
 fi
 
 # If this is a source checkout then call autoreconf with error as well
-if test -d .git; then
+if test -e .git; then
   WARNINGS="all,error"
   # touch fips files for non fips distribution
   touch ./ctaocrypt/src/fips.c
diff --git a/m4/ax_vcs_checkout.m4 b/m4/ax_vcs_checkout.m4
index 8047b65ec..4636b58ed 100644
--- a/m4/ax_vcs_checkout.m4
+++ b/m4/ax_vcs_checkout.m4
@@ -45,7 +45,10 @@
 #  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 #  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-#serial 6
+#serial 6.1
+#
+# Added tweak for git. The base repo's .git is a directory. Any worktree's
+# .git is a file. Use -e to check for either dir or file.
 
 AC_DEFUN([AX_VCS_SYSTEM],
     [AC_PREREQ([2.63])dnl
@@ -54,7 +57,7 @@ AC_DEFUN([AX_VCS_SYSTEM],
       AS_IF([test -d ".bzr"],[ac_cv_vcs_system="bazaar"])
       AS_IF([test -d ".svn"],[ac_cv_vcs_system="svn"])
       AS_IF([test -d ".hg"],[ac_cv_vcs_system="mercurial"])
-      AS_IF([test -d ".git"],[ac_cv_vcs_system="git"])
+      AS_IF([test -e ".git"],[ac_cv_vcs_system="git"])
       ])
     AC_DEFINE_UNQUOTED([VCS_SYSTEM],["$ac_cv_vcs_system"],[VCS system])
     ])