Nuke as many warnings as possible, and several globals as well

- Warnings completely suppressed for the included TinyXML and gzstream libraries
- Parentheses warnings are now errors, since there were several that looked like bugs
- Ditto for dangling else warnings

Some of these warnings were actually bugs:
- Town wandering monsters would have never spawned, because the code to do so was accidentally nested within a check for overall_mode == MODE_OUTDOORS
---> boe.monster.cpp, lines 105-137
- Monster's behaviour with respect to elemental fields did not correctly depend on their immunities (this is the same precedence issue Sylae messed up fixing in the Windows code)
---> boe.monsters.cpp, lines 345-359
- Display of damage blocked by armour appeared to be incorrect (needs verification)
---> boe.newgraph.cpp, line 1079
- Three-choice dialogs probably weren't dealing with unusual button types correctly, though that's a minor point since they aren't expected to use such buttons

osx/classes/location.cpp

@@ -175,7 +175,7 @@ rectangle rect(location tl, location br){
 	return rectangle(tl,br);
 }
 
-rectangle rect(char top, char left, char bottom, char right){
+rectangle rect(int top, int left, int bottom, int right) {
 	return rectangle(top, left, bottom, right);
 }
 

osx/classes/monster.cpp

@@ -130,7 +130,7 @@ cCreature& cCreature::operator = (legacy::creature_data_type old){
 	return *this;
 }
 
-cMonster::cAttack::operator int(){
+cMonster::cAttack::operator int() const {
 	return dice * 100 + sides;
 }
 
@@ -140,7 +140,7 @@ cMonster::cAttack& cMonster::cAttack::operator=(int n){
 	return *this;
 }
 
-std::ostream& operator<<(std::ostream& out, cMonster::cAttack& att) {
+std::ostream& operator<<(std::ostream& out, const cMonster::cAttack& att) {
 	out << int(att.dice) << 'd' << int(att.sides);
 	return out;
 }
@@ -174,6 +174,7 @@ std::istream& operator >> (std::istream& in, eRace& e){
 
 extern cUniverse univ;
 extern cScenario scenario;
+// TODO: Any setup where "x = x" does something is probably a bad idea...
 cCreature& cCreature::operator = (const cCreature& other){ // replaces return_monster_template() from boe.monsters.cpp
 	id = other.id;
 	number = other.number;
@@ -216,6 +217,8 @@ cMonster::cAbility::operator std::string(){
 	std::ostringstream sout;
 	short i = 0;
 	switch(abil){
+		case MONST_NO_ABIL:
+			break;
 		case MONST_THROWS_DARTS:
 			sout << "Throws darts (" << extra1 << 'd' << extra2 << ')';
 			break;
@@ -472,7 +475,7 @@ cMonster::cAbility::operator std::string(){
 			sout << "Unusual ability";
 			break;
 	}
-	return "*ERROR INVALID ABILITY*";
+	return sout.str();
 }
 
 std::string cMonster::getAbil1Name() {
@@ -496,11 +499,11 @@ bool cMonster::hasAbil(eMonstAbil what, unsigned char* x1, unsigned char* x2){
 	return false;
 }
 
-void cMonster::writeTo(std::ostream& file) {
+void cMonster::writeTo(std::ostream& /*file*/) {
 	// TODO: Implement this (low priority since only used for exported summons)
 }
 
-void cMonster::readFrom(std::istream& file) {
+void cMonster::readFrom(std::istream& /*file*/) {
 	// TODO: Implement this (low priority since only used for exported summons)
 }
 

osx/classes/monster.h

@@ -97,7 +97,7 @@ public:
 	struct cAttack{
 		unsigned char dice, sides, type;
 		// TODO: Remove the need for these operators by changing the code that uses them
-		operator int();
+		operator int() const;
 		cAttack& operator=(int n);
 	};
 	struct cAbility{
@@ -189,5 +189,5 @@ std::ostream& operator << (std::ostream& out, eRace& e);
 std::istream& operator >> (std::istream& in, eRace& e);
 std::ostream& operator << (std::ostream& out, eMonstAbil& e);
 std::istream& operator >> (std::istream& in, eMonstAbil& e);
-std::ostream& operator<<(std::ostream& out, cMonster::cAttack& att);
+std::ostream& operator<<(std::ostream& out, const cMonster::cAttack& att);
 #endif

osx/classes/tmpltown.cpp

@@ -13,15 +13,15 @@
 
 #include "classes.h"
 
-ter_num_t& cBigTemplTown::terrain(size_t x, size_t y){
+ter_num_t& cBigTemplTown::terrain(size_t /*x*/, size_t /*y*/){
 	return  _terrain[0][0]; // TODO: will need to calculate the terrain somehow
 }
 
-void cBigTemplTown::writeTerrainTo(std::ostream& file) {
+void cBigTemplTown::writeTerrainTo(std::ostream& /*file*/) {
 	// TODO: Write out the terrain somehow;
 }
 
-void cBigTemplTown::readTerrainFrom(std::istream& file) {
+void cBigTemplTown::readTerrainFrom(std::istream& /*file*/) {
 	// TODO: Read in the terrain somehow
 }
 

osx/classes/town.cpp

@@ -14,9 +14,9 @@
 #include "classes.h"
 #include "oldstructs.h"
 
-void cTown::append(legacy::big_tr_type& old){}
-void cTown::append(legacy::ave_tr_type& old){}
-void cTown::append(legacy::tiny_tr_type& old){}
+void cTown::append(legacy::big_tr_type&){}
+void cTown::append(legacy::ave_tr_type&){}
+void cTown::append(legacy::tiny_tr_type&){}
 
 cTown& cTown::operator = (legacy::town_record_type& old){
 	int i;
@@ -82,7 +82,7 @@ cTown& cTown::operator = (legacy::town_record_type& old){
 cTown::cTown(){}
 
 short max_dim[3] = {64,48,32};
-cTown::cTown(short size){
+cTown::cTown(short){
 	short i,s;
 	location d_loc(100,0);
 	cTown::cWandering d_wan = {0,0,0,0};