diff --git a/configure b/configure
index 2b31de150..2436faf12 100755
--- a/configure
+++ b/configure
@@ -3828,7 +3828,9 @@ then
   $as_echo "#define MAX_WORKERS 1" >>confdefs.h
 
 else
-  $as_echo "#define MAX_WORKERS \$yap_cv_max_workers" >>confdefs.h
+  cat >>confdefs.h <<_ACEOF
+#define MAX_WORKERS $yap_cv_max_workers
+_ACEOF
 
 fi
 
diff --git a/configure.in b/configure.in
index d8d4255b7..75975dabc 100755
--- a/configure.in
+++ b/configure.in
@@ -318,7 +318,7 @@ if test "$or-parallelism" = no
 then
   AC_DEFINE(MAX_WORKERS,1)
 else
-  AC_DEFINE(MAX_WORKERS,$yap_cv_max_workers)
+  AC_DEFINE_UNQUOTED(MAX_WORKERS,$yap_cv_max_workers)
 fi
 
 if test "$threads" = no