[Runtime] Update cflags and fix warnings accordingly.

Make.config

@@ -190,7 +190,7 @@ IOS_CXX=$(XCODE_CXX)
 SIMULATOR_BIN_PATH=$(XCODE_DEVELOPER_ROOT)/Platforms/iPhoneSimulator.platform/Developer/usr/bin
 SIMULATOR_CC=$(IOS_CC)
 
-CFLAGS= -Wall -fms-extensions -Wno-format-security -Wsign-compare -Wshorten-64-to-32 -Wsign-conversion -Wdeprecated -Wuninitialized -fstack-protector-strong
+CFLAGS= -Wall -fms-extensions -Werror -Wconversion -Wdeprecated -Wuninitialized -fstack-protector-strong
 
 ifdef ENABLE_BITCODE_ON_IOS
 BITCODE_CFLAGS=-fembed-bitcode-marker

runtime/runtime.m

@@ -495,7 +495,7 @@ void xamarin_framework_peer_unlock ()
 // The XamarinExtendedObject protocol is just to avoid a 
 // compiler warning (no 'xamarinGetGChandle' selector found).
 @protocol XamarinExtendedObject
--(int) xamarinGetGCHandle;
+-(uint32_t) xamarinGetGCHandle;
 -(void) xamarinSetGCHandle: (uint32_t) gc_handle;
 @end
 
@@ -2809,7 +2809,7 @@ -(void) dealloc
  */
 
 @implementation NSObject (NonXamarinObject)
--(int) xamarinGetGCHandle
+-(uint32_t) xamarinGetGCHandle
 {
 	// COOP: no managed memory access: any mode.
 	return 0;

runtime/xamarin/runtime.h

@@ -297,7 +297,7 @@ class XamarinObject {
 @end
 
 @interface NSObject (NonXamarinObject)
--(int) xamarinGetGCHandle;
+-(uint32_t) xamarinGetGCHandle;
 @end
 #endif
 

tests/test-libraries/libtest.m

@@ -506,7 +506,7 @@ -(void) setProtocol
 
 -(void) completedSetProtocol: (id<ProtocolAssignerProtocol>) value
 {
-	assert (!"THIS FUNCTION SHOULD BE OVERRIDDEN");
+	assert (false); // "THIS FUNCTION SHOULD BE OVERRIDDEN";
 }
 @end
 
@@ -602,7 +602,7 @@ + (void)setTestClass:(Class) value {
 
 -(void) classCallback: (void (^)(int32_t magic_number))completionHandler
 {
-	assert (!"THIS FUNCTION SHOULD BE OVERRIDDEN");
+	assert (false); // THIS FUNCTION SHOULD BE OVERRIDDEN
 }
 
 -(void) callClassCallback
@@ -730,7 +730,7 @@ -(void) callAssertMainThreadBlockReleaseCallbackQOS
 
 -(void) assertMainThreadBlockReleaseCallback: (innerBlock) completionHandler
 {
-	assert (!"THIS FUNCTION SHOULD BE OVERRIDDEN");
+	assert (false); // THIS FUNCTION SHOULD BE OVERRIDDEN
 }
 
 -(void) testFreedBlocks
@@ -756,7 +756,10 @@ +(int) calledBlockCount
 
 static void block_called ()
 {
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
 	OSAtomicIncrement32 (&called_blocks);
+#pragma clang diagnostic pop
 }
 
 +(void) callProtocolWithBlockProperties: (id<ProtocolWithBlockProperties>) obj required: (bool) required instance: (bool) instance;
@@ -821,7 +824,10 @@ +(void) setProtocolWithBlockProperties: (id<ProtocolWithBlockProperties>) obj re
 @implementation FreedNotifier
 -(void) dealloc
 {
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
 	OSAtomicIncrement32 (&freed_blocks);
+#pragma clang diagnostic pop
 	[super dealloc];
 }
 @end

tools/common/StaticRegistrar.cs

@@ -2523,9 +2523,9 @@ string GetObjCSignature (ObjCMethod method, List<Exception> exceptions)
 			else if (method.CurrentTrampoline == Trampoline.Release)
 				return "-(void) release";
 			else if (method.CurrentTrampoline == Trampoline.GetGCHandle)
-				return "-(int) xamarinGetGCHandle";
+				return "-(uint32_t) xamarinGetGCHandle";
 			else if (method.CurrentTrampoline == Trampoline.SetGCHandle)
-				return "-(void) xamarinSetGCHandle: (int) gchandle";
+				return "-(void) xamarinSetGCHandle: (uint32_t) gchandle";
 #if MONOMAC
 			else if (method.CurrentTrampoline == Trampoline.CopyWithZone1 || method.CurrentTrampoline == Trampoline.CopyWithZone2)
 				return "-(id) copyWithZone: (NSZone *)zone";
@@ -3154,14 +3154,14 @@ void Specialize (AutoIndentStringBuilder sb, ObjCMethod method, List<Exception>
 				sb.WriteLine ();
 				return;
 			case Trampoline.GetGCHandle:
-				sb.WriteLine ("-(int) xamarinGetGCHandle");
+				sb.WriteLine ("-(uint32_t) xamarinGetGCHandle");
 				sb.WriteLine ("{");
 				sb.WriteLine ("return __monoObjectGCHandle.gc_handle;");
 				sb.WriteLine ("}");
 				sb.WriteLine ();
 				return;
 			case Trampoline.SetGCHandle:
-				sb.WriteLine ("-(void) xamarinSetGCHandle: (int) gc_handle");
+				sb.WriteLine ("-(void) xamarinSetGCHandle: (uint32_t) gc_handle");
 				sb.WriteLine ("{");
 				sb.WriteLine ("__monoObjectGCHandle.gc_handle = gc_handle;");
 				sb.WriteLine ("__monoObjectGCHandle.native_object = self;");