diff --git a/Makefile b/Makefile
index 6d42d74082a59a70cc623aea293cb8dff7fde185..ea8622a26a63f152040f60497465af279b442188 100644
--- a/Makefile
+++ b/Makefile
@@ -206,7 +206,7 @@ clean-tests: purge-tests
 
 # Generates all dune files used for testing
 .PHONY: run-ptests
-run-ptests: config.sed purge-tests
+run-ptests: config.sed purge-tests ptests/ptests.exe ptests/wtests.exe
 	$(PTESTS) $(TEST_DIRS)
 
 # run tests of for all configurations (requires all dune files)
diff --git a/ptests/wtests.ml b/ptests/wtests.ml
index 86a1ca9b351da9dd69c3ff801f944ffd68c8884b..40ccc005caa28e607f9808d970dfad82e5b98838 100644
--- a/ptests/wtests.ml
+++ b/ptests/wtests.ml
@@ -40,7 +40,7 @@ end
 (* ------------------------------- *)
 
 let pp_json fmt json =
-  Format.fprintf fmt "%% dune build @@%s" json
+  Format.fprintf fmt "%% dune build @@%S" json
 
 let fail ~json s info =
   Format.printf "%a: Error - %s@.%% Aborting: %s@." pp_json json s info ;
@@ -151,7 +151,7 @@ let compare_files ~json ~error~result oracle =
   let not_generated = not (Sys.file_exists result) in
   if not_generated then
     Format.printf "%a: missing target %S@." pp_json json result;
-  let cmd = Format.sprintf "%s %s %s" (if !verbosity > 0  then diff_cmd else cmp_cmd) oracle result in
+  let cmd = Format.sprintf "%s %S %S" (if !verbosity > 0  then diff_cmd else cmp_cmd) oracle result in
   if !verbosity > 0  then Format.printf "%% Run compare command: %s@." cmd;
   let ret_code = launch cmd in
   let is_ko = ret_code <> 0 in
diff --git a/tests/ptests_config b/tests/ptests_config
index c1497a20507906a6bca5274a64d244af646e8f07..0773e60a66fd2c2363b45d6f6f0e6ae768496c3c 100644
--- a/tests/ptests_config
+++ b/tests/ptests_config
@@ -5,9 +5,9 @@
 
 DEFAULT_SUITES= callgraph cil constant_propagation float idct impact
 # todo:
-IGNORE= DEFAULT_SUITES= builtins compliance dynamic syntax
+IGNORE= DEFAULT_SUITES= builtins compliance dynamic
 
-DEFAULT_SUITES= occurrence pretty_printing rte_manual
+DEFAULT_SUITES= occurrence pretty_printing rte_manual syntax
 # todo:
 IGNORE= DEFAULT_SUITES= journal libc metrics pdg rte