diff --git a/astronaut/astronaut b/astronaut/astronaut
index d8a0f9a..95403a8 100755
--- a/astronaut/astronaut
+++ b/astronaut/astronaut
@@ -165,19 +165,18 @@ download() {
     [ "$3" ] && local filename="$3" || local filename="$(basename $(echo "$1" | cut -d? -f1))"
     local path="$dir_source/$name/$filename"
 
-    [ "$2" -a -f "$path" ] && local checksum="$(_mksum "$path")" || true
-
-    if [ ! -e "$path" -o "$checksum" != "$2" ]; then
+    if [ ! -e "$path" -o "$(_mksum "$path")" != "$2" ]; then
         _msg "Downloading $filename"
 
         [ "$4" ] && local cmd="$4" || local cmd="$cmd_download"
         eval $(echo "$cmd" | sed -e "s/{dst}/'$(safe_sed "$path")'/g" -e "s/{src}/'$(safe_sed "$1")'/g")
 
-        checksum="$(_mksum "$path")"
-        if [ "$2" -a "$checksum" != "$2" ]; then
+        if [ "$2" -a "$(_mksum "$path")" != "$2" ]; then
             _msg "Checksum: $checksum"
             _exiterr 'Checksum failed'
         fi
+    elif [ ! -f "$path" ]; then
+        _exiterr "'$path' exists but isn't a file?"
     fi
 }
 
diff --git a/satellites/android-tools.sat b/satellites/android-tools.sat
index 4c178c8..db4709a 100644
--- a/satellites/android-tools.sat
+++ b/satellites/android-tools.sat
@@ -1,7 +1,7 @@
 import 'vcs/git'
 
 name=android-tools
-version=7.1.2_r6
+version=7.1.2_r8
 update_url='https://android.googlesource.com/platform/system/core/+refs'
 update_names="<a href=\"/platform/system/core/+/android-$version\">"