From e677a675b057fedcd0acd41f04f5c3749bcd2af0 Mon Sep 17 00:00:00 2001
From: Mart Lubbers <mart@martlubbers.net>
Date: Thu, 17 May 2018 15:33:39 +0200
Subject: [PATCH] Fix memory leaks and verbosify reduction

---
 lambda.y |  1 +
 main.c   |  4 ++--
 reduce.c | 21 +++++++++++++--------
 3 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/lambda.y b/lambda.y
index cb8259a..1dbcaaf 100644
--- a/lambda.y
+++ b/lambda.y
@@ -1,3 +1,4 @@
+%define parse.error verbose
 %{
 #include "lambda.h"
 #include "lambda.tab.h"
diff --git a/main.c b/main.c
index ac9bea3..22e4d66 100644
--- a/main.c
+++ b/main.c
@@ -12,14 +12,14 @@ extern struct lambda *result;
 int main()
 {
 	int r = yyparse();
-	int maxdepth = 100;
+	int maxdepth = 10000;
 	if(r == 0){
 		printf("     ");
 		lambda_reduce(result, result, &maxdepth);
 		lambda_print(result, NULL);
-		lambda_free(result);
 	}
 	yylex_destroy();
+	lambda_free(result);
 	decls_free();
 	return r;
 }
diff --git a/reduce.c b/reduce.c
index 429b038..7106743 100644
--- a/reduce.c
+++ b/reduce.c
@@ -41,17 +41,18 @@ void lambda_alpha(struct lambda *expr, struct lambda *ident)
 
 void lambda_beta(struct lambda *ident, struct lambda *body, struct lambda *target, struct lambda *total)
 {
-	struct lambda cpy;
+	struct lambda *cpy;
 	switch(body->which){
 	case lambda_ident:
 		if(lambda_ident_eq(body, ident)){
 			lambda_print(total, NULL);
 			printf("β -> ");
-			cpy = *copy(target);
+			cpy = copy(target);
 			free(body->data.identifier.ident);
 			if(total == body)
-				*total = cpy;
-			*body = cpy;
+				*total = *cpy;
+			*body = *cpy;
+			free(cpy);
 		}
 		break;
 	case lambda_abs:
@@ -79,7 +80,7 @@ void lambda_reduce(struct lambda *t, struct lambda *total, int *maxdepth)
 	case lambda_ident:
 		break;
 	case lambda_abs:
-		lambda_reduce(t->data.abstraction.expr, total, maxdepth);
+//		lambda_reduce(t->data.abstraction.expr, total, maxdepth);
 		break;
 	case lambda_app:
 		t1 = t->data.application.expr1;
@@ -89,10 +90,14 @@ void lambda_reduce(struct lambda *t, struct lambda *total, int *maxdepth)
 			lambda_print(total, t);
 			printf("β -> ");
 			lambda_beta(t1, t1->data.abstraction.expr, t2, total);
-			(*maxdepth)--;
+			lambda_free(t2);
+			t2 = copy(t1->data.abstraction.expr);
 			if(total == t)
-				*total = *t1->data.abstraction.expr;
-			*t = *t1->data.abstraction.expr;
+				*total = *t2;
+			lambda_free(t1);
+			*t = *t2;
+			free(t2);
+			(*maxdepth)--;
 			lambda_reduce(t, total, maxdepth);
 		}
 		break;
-- 
2.20.1