diff --git a/ApplicationController.h b/ApplicationController.h
index dc3da26..64d1c13 100644
--- a/ApplicationController.h
+++ b/ApplicationController.h
@@ -12,7 +12,7 @@
 @class PBCLIProxy;
 @class PBCloneRepositoryPanel;
 
-@interface ApplicationController : NSObject
+@interface ApplicationController : NSObject <NSWindowDelegate>
 {
 	IBOutlet NSWindow *window;
 	IBOutlet id firstResponder;
diff --git a/DBPrefsWindowController.h b/DBPrefsWindowController.h
index 5cb711e..b013ac7 100644
--- a/DBPrefsWindowController.h
+++ b/DBPrefsWindowController.h
@@ -42,7 +42,7 @@
 #import <Cocoa/Cocoa.h>
 
 
-@interface DBPrefsWindowController : NSWindowController {
+@interface DBPrefsWindowController : NSWindowController <NSAnimationDelegate, NSToolbarDelegate> {
 	NSMutableArray *toolbarIdentifiers;
 	NSMutableDictionary *toolbarViews;
 	NSMutableDictionary *toolbarItems;
diff --git a/DBPrefsWindowController.m b/DBPrefsWindowController.m
index 58b4d6b..c5dbc08 100644
--- a/DBPrefsWindowController.m
+++ b/DBPrefsWindowController.m
@@ -370,7 +370,7 @@ static DBPrefsWindowController *_sharedPrefsWindowController = nil;
 	NSEnumerator *subviewsEnum = [[contentSubview subviews] reverseObjectEnumerator];
 
 		// This is our visible view. Just get past it.
-	subview = [subviewsEnum nextObject];
+	[subviewsEnum nextObject];
 
 		// Remove everything else. There should be just one, but
 		// if the user does a lot of fast clicking, we might have
diff --git a/PBCLIProxy.m b/PBCLIProxy.m
index e6f2e50..08a87fe 100644
--- a/PBCLIProxy.m
+++ b/PBCLIProxy.m
@@ -80,9 +80,11 @@
                                    suggestion], NSLocalizedFailureReasonErrorKey,
                                   recoveryInfo, NSLocalizedRecoverySuggestionErrorKey, nil];
 
-        *error = [NSError errorWithDomain:PBCLIProxyErrorDomain code:errCode userInfo:userInfo];
-
-        fprintf(stderr, "\t%s\n", [[*error localizedFailureReason] UTF8String]);
+        if (error)
+        {
+            *error = [NSError errorWithDomain:PBCLIProxyErrorDomain code:errCode userInfo:userInfo];
+            fprintf(stderr, "\t%s\n", [[*error localizedFailureReason] UTF8String]);
+        }
     }
 
     // NSLog(@"document = %@ at path = %@", document, repositoryPath);
diff --git a/PBGitRevisionCell.m b/PBGitRevisionCell.m
index 0a129f1..79a26e7 100644
--- a/PBGitRevisionCell.m
+++ b/PBGitRevisionCell.m
@@ -189,7 +189,7 @@
 {
 	[[NSColor blackColor] setStroke];
 
-	NSRect lastRect;
+	NSRect lastRect = NSMakeRect(0, 0, 0, 0);
 	int index = 0;
 	for (NSValue *rectValue in [self rectsForRefsinRect:*refRect])
 	{
diff --git a/PBGitSidebarController.h b/PBGitSidebarController.h
index 52357ca..1ae59c0 100644
--- a/PBGitSidebarController.h
+++ b/PBGitSidebarController.h
@@ -14,7 +14,7 @@
 @class PBGitCommitController;
 @class ApplicationController;
 
-@interface PBGitSidebarController : PBViewController {
+@interface PBGitSidebarController : PBViewController <NSOutlineViewDelegate> {
 	IBOutlet NSWindow *window;
 	IBOutlet NSOutlineView *sourceView;
 	IBOutlet NSView *sourceListControlsView;
diff --git a/PBGitWindowController.h b/PBGitWindowController.h
index dec5c9c..78a1c98 100644
--- a/PBGitWindowController.h
+++ b/PBGitWindowController.h
@@ -11,7 +11,7 @@
 
 @class PBViewController, PBGitSidebarController, PBGitHistoryController;
 
-@interface PBGitWindowController : NSWindowController {
+@interface PBGitWindowController : NSWindowController <NSWindowDelegate> {
 	__weak PBGitRepository* repository;
 
 	__weak PBViewController *contentController;
diff --git a/PBRepositoryDocumentController.m b/PBRepositoryDocumentController.m
index cbc777b..35dda88 100644
--- a/PBRepositoryDocumentController.m
+++ b/PBRepositoryDocumentController.m
@@ -72,7 +72,8 @@
         NSString * reason = @"It does not appear to be a git repository.";
         NSString * suggestion = @"Make sure there really is a \u201c.git\u201d folder somewhere in the path hierarchy you are trying to open";
         NSDictionary * errInfo = [NSDictionary dictionaryWithObjectsAndKeys:reason, NSLocalizedFailureReasonErrorKey, suggestion, NSLocalizedRecoverySuggestionErrorKey, nil];
-        *outError = [NSError errorWithDomain:NSCocoaErrorDomain code:PBNotAGitRepositoryErrorCode userInfo:errInfo];
+        if (outError)
+            *outError = [NSError errorWithDomain:NSCocoaErrorDomain code:PBNotAGitRepositoryErrorCode userInfo:errInfo];
         return nil;
     }
     return [super openDocumentWithContentsOfURL:absoluteURL display:displayDocument error:outError];
diff --git a/gitx_askpasswd_main.m b/gitx_askpasswd_main.m
index 3e77140..1da6044 100644
--- a/gitx_askpasswd_main.m
+++ b/gitx_askpasswd_main.m
@@ -18,7 +18,7 @@
 #define	PASSLABELHEIGHT			16.0
 
 
-@interface GAPAppDelegate : NSObject
+@interface GAPAppDelegate : NSObject <NSApplicationDelegate>
 {
 	NSPanel*			mPasswordPanel;
 	NSSecureTextField*	mPasswordField;