diff --git a/src/cr2image.cpp b/src/cr2image.cpp
index df178ec2..23270db3 100644
--- a/src/cr2image.cpp
+++ b/src/cr2image.cpp
@@ -280,6 +280,7 @@ namespace Exiv2 {
             buf.pData_[0] = 0x4d;
             buf.pData_[1] = 0x4d;
             break;
+        case asciiBytes:
         case invalidByteOrder:
             assert(false);
             break;
diff --git a/src/orfimage.cpp b/src/orfimage.cpp
index b0536bcc..41699439 100644
--- a/src/orfimage.cpp
+++ b/src/orfimage.cpp
@@ -277,6 +277,7 @@ namespace Exiv2 {
             buf.pData_[0] = 0x4d;
             buf.pData_[1] = 0x4d;
             break;
+        case asciiBytes:
         case invalidByteOrder:
             assert(false);
             break;
diff --git a/src/tiffvisitor.cpp b/src/tiffvisitor.cpp
index 964f0479..8bc6d443 100644
--- a/src/tiffvisitor.cpp
+++ b/src/tiffvisitor.cpp
@@ -363,6 +363,7 @@ namespace Exiv2 {
         case bigEndian:
             exifData_["Exif.MakerNote.ByteOrder"] = "MM";
             break;
+        case asciiBytes:
         case invalidByteOrder:
             assert(object->byteOrder() != invalidByteOrder);
             break;