diff --git a/macros.ghc b/macros.ghc
index 16c0456..bd8c190 100644
--- a/macros.ghc
+++ b/macros.ghc
@@ -127,7 +127,7 @@ fi\
 
 # workaround Cabal bug causing executable extra-source-files
 %ghc_fix_doc_perms\
-for f in $(ls | grep -i -e "^\(ANNOUNCE\|AUTHORS\|CHANGELOG\|CHANGES\|CONTRIBUTORS\|README\|TODO\)"); do\
+for f in $(ls | grep -i -e '^\\(ANNOUNCE\\|AUTHORS\\|CHANGELOG\\|CHANGES\\|CONTRIBUTORS\\|README\\|TODO\\)'); do\
 if [ -x $f ]; then chmod a-x $f; fi\
 done\
 %{nil}