diff --git a/InstructionSets/x86/Decoder.cpp b/InstructionSets/x86/Decoder.cpp
index 75be5cdc1..f354816bd 100644
--- a/InstructionSets/x86/Decoder.cpp
+++ b/InstructionSets/x86/Decoder.cpp
@@ -716,6 +716,8 @@ std::pair<int, typename Decoder<model>::InstructionT> Decoder<model>::decode(con
 			case ModRegRMFormat::MemReg_Seg:
 				// The 16-bit chips have four segment registers;
 				// the 80386 onwards has six.
+
+				// TODO: the 8086, at least, decodes something. Probably just the low two bits?
 				if(!is_32bit(model) && reg > 3) {
 					undefined();
 				} else if(reg > 5) {
diff --git a/InstructionSets/x86/Instruction.cpp b/InstructionSets/x86/Instruction.cpp
index 1a2b36e20..57b76c04a 100644
--- a/InstructionSets/x86/Instruction.cpp
+++ b/InstructionSets/x86/Instruction.cpp
@@ -155,6 +155,7 @@ bool InstructionSet::x86::mnemonic_implies_data_size(Operation operation) {
 		case Operation::STOS:
 		case Operation::JMPrel:
 		case Operation::JMPfar:
+		case Operation::LEA:
 			return true;
 	}
 }
diff --git a/OSBindings/Mac/Clock SignalTests/8088Tests.mm b/OSBindings/Mac/Clock SignalTests/8088Tests.mm
index 184fd8874..4fe2d2bee 100644
--- a/OSBindings/Mac/Clock SignalTests/8088Tests.mm	
+++ b/OSBindings/Mac/Clock SignalTests/8088Tests.mm	
@@ -98,6 +98,9 @@ std::string to_string(InstructionSet::x86::DataPointer pointer, const Instructio
 						}
 						[[fallthrough]];
 					case 2:
+						// TODO: this mismatches some tests because it doesn't eliminate sign extensions.
+						// But when is it permissible to eliminate sign extensions? Always for now, and deal
+						// with it when testing actual execution?
 						if(!(instruction.offset() & 0xff00)) {
 							stream << '+' << to_hex(instruction.offset(), 2);
 							break;