4 files changed, 13 insertions, 0 deletions
diff --git a/hence.c b/hence.c
index fbcb917..1fcd835 100644
--- a/hence.c
+++ b/hence.c
@@ -24,6 +24,9 @@ int main(int argc, char **argv) {
 	}
 
 	struct token *tok = lex_file(argv[1], fd);
+	if (!tok) {
+		return 1;
+	}
 	int p = parse(argv[1], fd, tok);
 
 //	gate_set_input("a", LOGIC_LOW);
diff --git a/lex.c b/lex.c
index 6777e42..19a7716 100644
--- a/lex.c
+++ b/lex.c
@@ -232,12 +232,17 @@ lex_line(void) {
 
 struct token *
 lex_file(const char *filename_local, FILE *fd_local) {
+	struct token start;
+
 	filename = filename_local;
 	fd = fd_local;
 
 	line_number = 1;
 	tok_cursor = tok_start = NULL;
 
+	start.type = TOK_BEGIN;
+	add_token(start);
+
 	while (NULL != fgets(buf, sizeof(buf), fd)) {
 		column_number = 0;
 		if (lex_line()) {
diff --git a/parse.c b/parse.c
index d955bc4..fb7855e 100644
--- a/parse.c
+++ b/parse.c
@@ -131,6 +131,8 @@ parse(const char *fname, FILE *f, struct token *t) {
 	filename = fname;
 	cursor = t;
 
+	EXPECT_AND_DISCARD_CRITICAL(TOK_BEGIN);
+
 	/* Eat leading EOL tokens */
 	while (cursor && cursor->type == TOK_EOL) {
 		kerchunk();
diff --git a/token.h b/token.h
index c00c870..453b554 100644
--- a/token.h
+++ b/token.h
@@ -4,6 +4,9 @@
 #define MAX_IDENT_LENGTH 128
 
 enum TOKEN_TYPE {
+	/* Nop token to indicate lexer success */
+	TOK_BEGIN,
+
 	/* Keywords */
 	TOK_MODULE,
 	TOK_INPUT,