diff --git a/Makefile b/Makefile
index 6340dcc..5b164f7 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 FILES = *.c */*.c
 LIBRARIES = -lpthread
 INCLUDES = -I. -I./parser/ -I./compiler/ -I./vm/ -I./tokenizer/ -I./misc/
-CFLAGS = -std=c99 -g
+CFLAGS = -std=c99 -g -Wall
 OUTFILE = jack-compiler
 
 main: ${FILES}
diff --git a/compiler/compiler-scopes.c b/compiler/compiler-scopes.c
index bb44e90..8276f50 100644
--- a/compiler/compiler-scopes.c
+++ b/compiler/compiler-scopes.c
@@ -26,11 +26,11 @@ SUBROUTDEC* getsubroutdec(SCOPE* s, const char* name);
 // Scope adding
 VAR* mkvar(char* type, char* name, bool primitive, DEBUGINFO* debug, MEMSEGMENT seg, int i);
 void addvar(SCOPE* s, VAR** dest, VAR* v);
-void addlocalvar(SCOPE* s, VARDEC* v, int i);
+void addlocalvar(SCOPE* s, VARDEC* v, int* i);
 void addstaticvar(COMPILER* c, SCOPE* s, CLASSVARDEC* v);
-void addfield(SCOPE* s, CLASSVARDEC* v, int i);
+void addfield(SCOPE* s, CLASSVARDEC* v, int* i);
 void addclassvardec(COMPILER* c, SCOPE* s, CLASSVARDEC* v, int* i);
-void addparameter(SCOPE* s, PARAMETER* p, int i);
+void addparameter(SCOPE* s, PARAMETER* p, int* i);
 
 // Error messages
 void doubledeclaration(const char* name, DEBUGINFO* d1, DEBUGINFO* d2) {
@@ -223,32 +223,33 @@ void addvar(SCOPE* s, VAR** dest, VAR* v) {
 	*dest = v;
 }
 
-void addlocalvar(SCOPE* s, VARDEC* v, int i) {
+void addlocalvar(SCOPE* s, VARDEC* v, int* i) {
 	STRINGLIST* currname = v->names;
 	while(currname != NULL) {
-		addvar(s, &(s->localvars), mkvar(v->type, currname->content, v->primitive, v->debug, local, i));
+		addvar(s, &(s->localvars), mkvar(v->type, currname->content, v->primitive, v->debug, local, *i));
 		currname = currname->next;
+		(*i)++;
 	}
 }
 
 void addstaticvar(COMPILER* c, SCOPE* s, CLASSVARDEC* v) {
-	pthread_mutex_lock(&(c->staticmutex));
-	static int count = 0;
-	int i = count;
-	count++;
-	pthread_mutex_unlock(&(c->staticmutex));
 	STRINGLIST* currname = v->base->names;
+	pthread_mutex_lock(&(c->staticmutex));
+	static int i = 0;
 	while(currname != NULL) {
 		addvar(s, &(s->staticvars), mkvar(v->base->type, currname->content, v->base->primitive, v->base->debug, staticseg, i));
 		currname = currname->next;
+		i++;
 	}
+	pthread_mutex_unlock(&(c->staticmutex));
 }
 
-void addfield(SCOPE* s, CLASSVARDEC* v, int i) {
+void addfield(SCOPE* s, CLASSVARDEC* v, int* i) {
 	STRINGLIST* currname = v->base->names;
 	while(currname != NULL) {
-		addvar(s, &(s->fields), mkvar(v->base->type, currname->content, v->base->primitive, v->base->debug, fieldseg, i));
+		addvar(s, &(s->fields), mkvar(v->base->type, currname->content, v->base->primitive, v->base->debug, fieldseg, *i));
 		currname = currname->next;
+		(*i)++;
 	}
 }
 
@@ -256,13 +257,13 @@ void addclassvardec(COMPILER* c, SCOPE* s, CLASSVARDEC* v, int* i) {
 	if(v->type == stat)
 		addstaticvar(c, s, v);
 	else {
-		addfield(s, v, *i);
-		*i++;
+		addfield(s, v, i);
 	}
 }
 
-void addparameter(SCOPE* s, PARAMETER* p, int i) {
-	addvar(s, &(s->parameters), mkvar(p->type, p->name, p->primitive, p->debug, arg, i));
+void addparameter(SCOPE* s, PARAMETER* p, int* i) {
+	addvar(s, &(s->parameters), mkvar(p->type, p->name, p->primitive, p->debug, arg, *i));
+	(*i)++;
 }
 
 // Group adding
@@ -277,8 +278,7 @@ void addclassvardecs(COMPILER* c, SCOPE* s, CLASSVARDEC* classvardecs) {
 void addlocalvars(SCOPE* s, VARDEC* localvars) {
 	int i = 0;
 	while(localvars != NULL) {
-		addlocalvar(s, localvars, i);
-		i++;
+		addlocalvar(s, localvars, &i);
 		localvars = localvars->next;
 	}
 }
@@ -286,8 +286,7 @@ void addlocalvars(SCOPE* s, VARDEC* localvars) {
 void addparameters(SCOPE* s, PARAMETER* params) {
 	int i = 0;
 	while(params != NULL) {
-		addparameter(s, params, i);
-		i++;
+		addparameter(s, params, &i);
 		params = params->next;
 	}
 }
diff --git a/compiler/compiler.c b/compiler/compiler.c
index e7673fe..33f3f24 100644
--- a/compiler/compiler.c
+++ b/compiler/compiler.c
@@ -85,15 +85,13 @@ LINE* mathopln(char op) {
 		char* tokens[] = { "call", "Math.divide", "2" };
 		return mksimpleln(tokens, strcount(tokens));
 	}
-	if(op == '*') {
-		char* tokens[] = { "call", "Math.multiply", "2" };
-		return mksimpleln(tokens, strcount(tokens));
-	}
+	char* tokens[] = { "call", "Math.multiply", "2" };
+	return mksimpleln(tokens, strcount(tokens));
 }
 
-LINEBLOCK* pushconstant(int n) {
+LINE* pushconstant(int n) {
 	char* tokens[] = { "push", "constant", itoa(n) };
-	return mklnblk(mksimpleln(tokens, strcount(tokens)));
+	return mksimpleln(tokens, strcount(tokens));
 }
 
 LINEBLOCK* pushunaryopterm(SCOPE* s, TERM* t) {
@@ -107,47 +105,77 @@ LINEBLOCK* pushunaryopterm(SCOPE* s, TERM* t) {
 	return blk;
 }
 
-LINEBLOCK* opvarraw(SCOPE* s, char* op, VAR* v) {
+LINE* opvarraw(SCOPE* s, char* op, VAR* v) {
 	char* tokens[] = { op, v->memsegment, itoa(v->index) };
-	return mklnblk(mksimpleln(tokens, strcount(tokens)));
+	return mksimpleln(tokens, strcount(tokens));
 }
 
-LINEBLOCK* opvar(SCOPE* s, char* op, const char* name) {
+LINE* opvar(SCOPE* s, char* op, const char* name) {
 	VAR* v = getvar(s, name);
 	return opvarraw(s, op, v);
 }
 
-LINEBLOCK* pushvarraw(SCOPE*s, VAR* v) {
+LINE* pushvarraw(SCOPE*s, VAR* v) {
 	return opvarraw(s, "push", v);
 }
 
-LINEBLOCK* pushvar(SCOPE* s, const char* name) {
+LINE* pushvar(SCOPE* s, const char* name) {
 	return opvar(s, "push", name);
 }
 
-LINEBLOCK* popvar(SCOPE* s, const char* name) {
+LINE* popvar(SCOPE* s, const char* name) {
 	return opvar(s, "pop", name);
 }
 
-LINEBLOCK* pushfalse() {
+LINE* pushfalse() {
 	return pushconstant(0);
 }
 
 LINEBLOCK* pushtrue() {
-	LINEBLOCK* blk = pushfalse();
+	LINEBLOCK* blk = mklnblk(pushfalse());
 	appendln(blk, onetoken("not"));
 	return blk;
 }
 
-LINEBLOCK* pushthis() {
-	char* pushthis[] = { "push", "pointer", "0" };
-	return mklnblk(mksimpleln(pushthis, strcount(pushthis)));
+LINE* pushthisadd() {
+	char* pushthisadd[] = { "push", "pointer", "0" };
+	return mksimpleln(pushthisadd, strcount(pushthisadd));
+}
+
+LINE* popthatadd() {
+	char* popthatadd[] = { "pop", "pointer", "1" };
+	return mksimpleln(popthatadd, strcount(popthatadd));
+}
+
+LINE* pushthatadd() {
+	char* pushthatadd[] = { "push", "pointer", "1" };
+	return mksimpleln(pushthatadd, strcount(pushthatadd));
+}
+
+LINE* popthat() {
+	char* popthat[] = { "pop", "that", "0" };
+	return mksimpleln(popthat, strcount(popthat));
+}
+
+LINE* pushthat() {
+	char* pushthat[] = { "push", "that", "0" };
+	return mksimpleln(pushthat, strcount(pushthat));
+}
+
+LINE* pushtemp() {
+	char* pushtemp[] = { "push", "temp", "0" };
+	return mksimpleln(pushtemp, strcount(pushtemp));
+}
+
+LINE* poptemp() {
+	char* poptemp[] = { "pop", "temp", "0" };
+	return mksimpleln(poptemp, strcount(poptemp));
 }
 
 LINEBLOCK* compilekeywordconst(SCOPE* s, TERM* t) {
 	if(!strcmp(t->string, "true")) return pushtrue();
-	if(!strcmp(t->string, "false")) return pushfalse();
-	if(!strcmp(t->string, "this")) return pushthis();
+	if(!strcmp(t->string, "false")) return mklnblk(pushfalse());
+	if(!strcmp(t->string, "this")) return mklnblk(pushthisadd());
 	eprintf("Unsupported keyword '%s'\n", t->string);
 	exit(1);
 }
@@ -185,16 +213,31 @@ LINEBLOCK* compilestrconst(char* str) {
 	appendlnbefore(blk, mksimpleln(mknew, strcount(mknew)));
 	appendlnbefore(blk, mksimpleln(strsize, strcount(strsize)));
 	free(strsize[2]);
+
+	return blk;
+}
+
+LINEBLOCK* compilearrayitem(SCOPE* s, TERM* t) {
+	LINEBLOCK* blk = compileexpression(s, t->array->exp);
+	appendln(blk, pushvar(s, t->array->name));
+
+	appendln(blk, onetoken("add"));
+
+	appendln(blk, popthatadd());
+	appendln(blk, pushthat());
+
+	return blk;
 }
 
 LINEBLOCK* compileterm(SCOPE* s, TERM* t) {
-	if(t->type == intconstant) return pushconstant(t->integer);
+	if(t->type == intconstant) return mklnblk(pushconstant(t->integer));
 	if(t->type == unaryopterm) return pushunaryopterm(s, t);
 	if(t->type == innerexpression) return compileexpression(s, t->expression);
-	if(t->type == varname) return pushvar(s, t->string);
+	if(t->type == varname) return mklnblk(pushvar(s, t->string));
 	if(t->type == subroutcall) return compilesubroutcall(s, t->call);
 	if(t->type == keywordconstant) return compilekeywordconst(s, t);
 	if(t->type == stringconstant) return compilestrconst(t->string);
+	return compilearrayitem(s, t);
 }
 
 LINEBLOCK* compileexpression(SCOPE* s, TERM* e) {
@@ -248,16 +291,15 @@ LINEBLOCK* compilesubroutcall(SCOPE* s, SUBROUTCALL* call) {
 
 	if(d->subroutclass == method) {
 		if(call->parentname == NULL)
-			blk = mergelnblks(pushthis(), blk);
+			appendlnbefore(blk, pushthisadd());
 		else
-			blk = mergelnblks(pushvarraw(s, v), blk);
+			appendlnbefore(blk, pushvarraw(s, v));
 	}
 
 	// void functions always return 0
 	// therefore must be thrown away
 	if(!strcmp(d->type, "void")) {
-		char* tokens[] = { "pop", "temp", "0" };
-		appendln(blk, mksimpleln(tokens, sizeof(tokens) / sizeof(char*)));
+		appendln(blk, poptemp());
 	}
 
 	return blk;
@@ -316,7 +358,6 @@ LINEBLOCK* compileif(COMPILER* c, SCOPE* s, IFSTATEMENT* st) {
 		appendln(blk, mksimpleln(endlabelln, strcount(endlabelln)));
 	}
 
-
 	return blk;
 }
 
@@ -351,9 +392,20 @@ LINEBLOCK* compilewhile(COMPILER* c, SCOPE* s, CONDSTATEMENT* w) {
 }
 
 LINEBLOCK* compilelet(SCOPE* s, LETSTATEMENT* l) {
-	// missing array ind
 	LINEBLOCK* blk = compileexpression(s, l->expression);
-	blk = mergelnblks(blk, popvar(s, l->varname));
+
+	if(l->arrayind != NULL) {
+		appendlnbefore(blk, onetoken("add"));
+		appendlnbefore(blk, pushvar(s, l->varname));
+		blk = mergelnblks(compileexpression(s, l->arrayind), blk);
+
+		appendln(blk, poptemp());
+		appendln(blk, popthatadd());
+		appendln(blk, pushtemp());
+		appendln(blk, popthat());
+	}
+	else
+		appendln(blk, popvar(s, l->varname));
 	return blk;
 }
 
diff --git a/main.c b/main.c
index cb2706a..0f80feb 100644
--- a/main.c
+++ b/main.c
@@ -135,6 +135,6 @@ int main(int argc, char* argv[]) {
 		currunit = currunit->next;
 	}
 
-	freeos();
+	//freeos();
 	return 0;
 }
diff --git a/misc/io.c b/misc/io.c
index 9788b63..d1d7542 100644
--- a/misc/io.c
+++ b/misc/io.c
@@ -78,11 +78,12 @@ bool isdotjack(char* f, int len) {
 bool isdir(char* f, int len) {
 	bool readsmt = false;
 	for(int i = len-1; i >= 0; i--) {
-		if(f[i] == '.')
+		if(f[i] == '.') {
 			if(readsmt)
 				return false;
 			else
 				continue;
+		}
 		if(f[i] == '/')
 			return 1;
 		readsmt = true;
diff --git a/misc/os.c b/misc/os.c
index 1092c2e..6985273 100644
--- a/misc/os.c
+++ b/misc/os.c
@@ -14,7 +14,7 @@ CLASS* addclass(const char* name) {
 	return c;
 }
 
-CLASS* adddec(CLASS* c, SUBROUTCLASS subroutclass, char* type, const char* name) {
+void adddec(CLASS* c, SUBROUTCLASS subroutclass, char* type, const char* name) {
 	SUBROUTDEC* dec = (SUBROUTDEC*)malloc(sizeof(SUBROUTDEC));
 	dec->class = c;
 	dec->subroutclass = subroutclass;
@@ -151,5 +151,5 @@ SUBROUTDEC* getossubroutdec(SUBROUTCALL* call) {
 	CLASS* c = getosclass(call->parentname);
 	if(c == NULL)
 		return NULL;
-	getsubroutdecinclass(c, call->name);
+	return getsubroutdecinclass(c, call->name);
 }
diff --git a/parser/parser-expressions.c b/parser/parser-expressions.c
index 55c6be0..bccca79 100644
--- a/parser/parser-expressions.c
+++ b/parser/parser-expressions.c
@@ -99,10 +99,11 @@ TERM* parsecalltermnullified(PARSER* p) {
 
 TERM* parsearrayterm(PARSER* p) {
 	TERM* t = mkterm(arrayitem);
-	t->string = p->current->token;
+	t->array = (ARRAY*)malloc(sizeof(ARRAY));
+	t->array->name = p->current->token;
 	next(p);
 	checkcontent(p, "[");
-	t->arrayexp = parseexpression(p);
+	t->array->exp = parseexpression(p);
 	checkcontent(p, "]");
 	return t;
 }
diff --git a/parser/parser-tree.h b/parser/parser-tree.h
index edf122d..dba2358 100644
--- a/parser/parser-tree.h
+++ b/parser/parser-tree.h
@@ -120,6 +120,11 @@ typedef enum {
 	varname, intconstant, stringconstant, keywordconstant, arrayitem, subroutcall, innerexpression, unaryopterm
 } TERMTYPE;
 
+typedef struct {
+	char* name;
+	struct term* exp;
+} ARRAY;
+
 typedef struct term {
 	TERMTYPE type;
 	union {
@@ -127,8 +132,8 @@ typedef struct term {
 		int integer;
 		struct subroutcall* call;
 		struct term* expression;
+		ARRAY* array;
 	};
-	struct term* arrayexp;
 	char op;
 	char unaryop;
 	struct term* next;