private boolean hasValidReturnType() {
		DataType returnType = functionData.getReturnInfo().getDataType();
		if (VoidDataType.isVoidDataType(returnType)) {
			return true;
		}
		if (returnType.getLength() <= 0) {
			statusText = "\"" + returnType.getName() +
				"\" is not allowed as a return type: Must be fixed size.";
			return false;
		}
		return true;
	}
Mark all storage conflicts identified by 
{@link VariableUtilities#checkVariableConflict(List, Variable, VariableStorage, VariableConflictHandler)}
@param conflicts parameters whose storage conflicts
@return return false to indicate conflicts have not been resolved and additional checks
should be disconctinued.
@see VariableConflictHandler
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/FunctionEditorModel.java