diff --git a/Makefile.src.in b/Makefile.src.in
index a6a1b57a36..4947760617 100644
--- a/Makefile.src.in
+++ b/Makefile.src.in
@@ -160,7 +160,7 @@ endif
 
 # Convert x:/... paths to /x/... for mingw
 ifeq ($(OS), MINGW)
-	@cat Makefile.dep.tmp | sed 's@\([a-zA-Z]\):/@/\1/@g' > Makefile.dep.tmp.mingw
+	@cat Makefile.dep.tmp | sed 's@\([a-zA-Z]\):\/@\/\1\/@g' > Makefile.dep.tmp.mingw
 	@cp Makefile.dep.tmp.mingw Makefile.dep.tmp
 	@rm -f Makefile.dep.tmp.mingw
 endif