Pass --always to git describe.

This generates a useful version string even for --depth=1 checkouts.
The option was added in git v1.6.6.

update_version

@@ -34,7 +34,8 @@ fi
 # -dirty from files that have been touched but are not actually altered in the
 # working dir.
 GIT_VERSION=$(cd "$SRCDIR" && git status > /dev/null 2>&1 \
-                           && git describe --tags --match 'v*' --dirty 2> /dev/null)
+                           && git describe --tags --match 'v*' \
+                                           --always --dirty 2> /dev/null)
 GIT_VERSION=${GIT_VERSION#v}
 
 if [ -n "$GIT_VERSION" ]; then

win32/genversion.bat

@@ -2,7 +2,7 @@
 
 setlocal enableextensions enabledelayedexpansion
 
-for /f %%v in ('git --git-dir="%~dp0..\.git" describe --tags --match "v*"') do set version=%%v
+for /f %%v in ('git --git-dir="%~dp0..\.git" describe --tags --match "v*" --always --dirty') do set version=%%v
 
 if not "%version%"=="" goto :gotversion
 
@@ -43,4 +43,4 @@ copy /y "%1_temp" "%1"
 
 :exit
 
-del "%1_temp"
+del "%1_temp"
\ No newline at end of file