diff --git a/Cargo.toml b/Cargo.toml
index d16c28f..6e2391f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -18,4 +18,4 @@ nan-preserving-float = "0.1.0"
 
 [dev-dependencies]
 assert_matches = "1.1"
-wabt = "0.3"
+wabt = "0.4"
diff --git a/tests/spec/mod.rs b/tests/spec/mod.rs
index 33c68b5..856b26b 100644
--- a/tests/spec/mod.rs
+++ b/tests/spec/mod.rs
@@ -22,7 +22,9 @@ run_test!("call_indirect", wasm_call_indirect);
 run_test!("comments", wasm_comments);
 run_test!("const", wasm_const);
 run_test!("conversions", wasm_conversions);
+run_test!("custom", wasm_custom);
 run_test!("custom_section", wasm_custom_section);
+run_test!("data", wasm_data);
 run_test!("elem", wasm_elem);
 run_test!("endianness", wasm_endianness);
 run_test!("exports", wasm_exports);
diff --git a/tests/spec/run.rs b/tests/spec/run.rs
index 80d312f..3f69cd8 100644
--- a/tests/spec/run.rs
+++ b/tests/spec/run.rs
@@ -1,5 +1,6 @@
 #![cfg(test)]
 
+use std::fs::File;
 use std::collections::HashMap;
 
 use wabt::script::{self, Action, Command, CommandKind, ScriptParser, Value};
@@ -340,7 +341,13 @@ pub fn spec(name: &str) {
 fn try_spec(name: &str) -> Result<(), Error> {
 	let mut spec_driver = SpecDriver::new();
 	let spec_script_path = format!("tests/spec/testsuite/{}.wast", name);
-	let mut parser = ScriptParser::from_file(spec_script_path).expect("Can't read spec script");
+
+	use std::io::Read;
+	let mut spec_source = Vec::new();
+	let mut spec_file = File::open(&spec_script_path).expect("Can't open file");
+	spec_file.read_to_end(&mut spec_source).expect("Can't read file");
+
+	let mut parser = ScriptParser::from_source_and_name(&spec_source, &format!("{}.wast", name)).expect("Can't read spec script");
 	let mut errors = vec![];
 
 	while let Some(Command { kind, line }) = parser.next()? {
@@ -364,7 +371,7 @@ fn try_spec(name: &str) -> Result<(), Error> {
 
 		match kind {
 			CommandKind::Module { name, module, .. } => {
-				load_module(&module.into_vec()?, &name, &mut spec_driver)
+				load_module(&module.into_vec(), &name, &mut spec_driver)
 					.expect("Failed to load module");
 			}
 			CommandKind::AssertReturn { action, expected } => {
@@ -446,14 +453,14 @@ fn try_spec(name: &str) -> Result<(), Error> {
 			CommandKind::AssertInvalid { module, .. }
 			| CommandKind::AssertMalformed { module, .. }
 			| CommandKind::AssertUnlinkable { module, .. } => {
-				let module_load = try_load(&module.into_vec()?, &mut spec_driver);
+				let module_load = try_load(&module.into_vec(), &mut spec_driver);
 				match module_load {
 					Ok(_) => panic!("Expected invalid module definition, got some module!"),
 					Err(_e) => {},
 				}
 			}
 			CommandKind::AssertUninstantiable { module, .. } => {
-				match try_load(&module.into_vec()?, &mut spec_driver) {
+				match try_load(&module.into_vec(), &mut spec_driver) {
 					Ok(_) => panic!("Expected error running start function at line {}", line),
 					Err(_e) => {},
 				}
diff --git a/tests/spec/testsuite b/tests/spec/testsuite
index c538faa..c6a690f 160000
--- a/tests/spec/testsuite
+++ b/tests/spec/testsuite
@@ -1 +1 @@
-Subproject commit c538faa43217146f458b9bc2d4b704d0a4d80963
+Subproject commit c6a690f89a0dda3c79700aa6377d8b5d8a970eba