diff --git a/ChangeLog b/ChangeLog
index 21042fc8783b9c122e34a9f141222b81838ebff3..41633c25cc3a1bbf0a60567729bba7ef4f8955f0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
 2013-12-03  Niels Möller  <nisse@lysator.liu.se>
 
+	* configure.ac (dummy-dep-files): Don't overwrite any existing
+	dependency files.
+
 	* x86_64/md5-compress.asm: New file, similar to the x86 version.
 	35% speedup.
 
diff --git a/configure.ac b/configure.ac
index 7ce4d5afa4526074c2e5cb02fa3b0ea462d0770c..a4deaae5ed7a9a9b8ce9245d284ee7a55052f7b0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -135,7 +135,10 @@ if test x$enable_dependency_tracking = xyes ; then
 
   AC_CONFIG_COMMANDS([dummy-dep-files],
   [(cd "$srcdir" && find . '(' -name '*.c' -o -name '*.cxx' ')' -print) \
- | sed 's/\.c\(xx\)\{0,1\}$//' | (while read f; do echo > "$f.o.d"; echo > "$f.po.d"; done)
+ | sed 's/\.c\(xx\)\{0,1\}$//' | (while read f; do \
+      test -f "$f.o.d" || echo > "$f.o.d"; \
+      test -f "$f.po.d" || echo > "$f.po.d"; \
+   done)
 ])
 fi