Cannot import message files from neighboring directory without adding '../src' to include paths

[edlongman]

Platform

• OMNeT++ version: 5.6.2
• OS: Windows (not relevant)

Describe the bug

When restructuring my project I tried to import a defs.msg with import common.defs into linklayer/linkLayerFrame.msg . defs.msg contains some definitions. The project looked like so:

+-src
    +-common
    |    +-defs.h
    |    +-defs.msg 
    |       +   cplusplus {{
    |       |       #include "common/defs.h"
    |       ╚   }}
    +-linklayer
        +-linkLayerFrame.msg

I had a problem with the message compiler, which would give the following error compilling
linkLayerFrame.msg
Error: cannot resolve import 'common.defs'

import common.defs;
import inet.common.packet.chunk.Chunk;
import inet.linklayer.common.MacAddress;

namespace msg_import_bug;

enum FrameType {
    DATA = 1;
    WU_ACK = 2;
};

class Datagram extends inet::FieldsChunk
{
    FrameType type;
    inet::MacAddress transmitterAddress;
    inet::MacAddress receiverAddress;
}

Which was being compiled with:
opp_msgc --msg6 -s _m.cc -MD -MP -MF ../out/gcc-release/src/linklayer/linkLayerFrame_m.h.d -I../../inet/src linklayer/linkLayerFrame.msg
To Reproduce
Attached project:
msg_import_bug.zip

Does not build unless ../src is added to C/C++ Build -> Paths and Symbols -> Includes

Problem
It is implied that, like .ned files messages will be included if they are within the directory structure of the same package. But this is not the case and it is not explained anywhere that the C/C++ include paths are relevant for the msgtool.

[Avian688]

Have the same error, any update on a fix?