Re: RE: "undefined reference" error message when using mkoctfile to create oct file

[Tatsuro MATSUOKA]

----- Original Message -----
> From: Yan Zhang 
> To: "help-octave
> Cc: 
> Date: 2017/2/22, Wed 11:15
> Subject: RE: RE: "undefined reference" error message when using mkoctfile to 
> create oct file
> 
>T hanks a lot for the kind help. I tried the dlltool and pexports and 
> successfully got a new lib file which I renamed as "usbdllnew.lib". 
> Unfortunately, I still couldn't make it work. Following are the messages I 
> got:
> 
> 
> -----------------------------------------------------
>>>  mkoctfile PowerMeter.cc -L. -lusbdllnew
> PowerMeter.o: In function `Z12CloseDevicesv':
> C:\Users\yan\Desktop\TestCam_Project\Oct_Src\cc/PowerMeter.cc:20: 
> undefined reference to address@hidden'
> PowerMeter.o: In function `Z11OpenDevicesi':
> C:\Users\yan\Desktop\TestCam_Project\Oct_Src\cc/PowerMeter.cc:30: 
> undefined reference to address@hidden'
> C:\Users\yan\Desktop\TestCam_Project\Oct_Src\cc/PowerMeter.cc:31: 
> undefined reference to address@hidden'
> PowerMeter.o: In function `Z4ReadiPciPm':
> C:\Users\yan\Desktop\TestCam_Project\Oct_Src\cc/PowerMeter.cc:41: 
> undefined reference to address@hidden'
> PowerMeter.o: In function `Z5WriteiPc':
> C:\Users\yan\Desktop\TestCam_Project\Oct_Src\cc/PowerMeter.cc:67: 
> undefined reference to address@hidden'
> collect2.exe: error: ld returned 1 exit status
> warning: mkoctfile exited with failure status
> warning: called from
>     mkoctfile at line 171 column 5
> -----------------------------------------------------
> 
> 
> Thanks,
> 
> Yan 
> 


Mmmm

Seeing error messages for "undefined reference to" like 
undefined reference to address@hidden'


Perhaps your problem is related @n (n is interger) symbol issue 
I googled and found the below 

Two possibilities. 

1. order of linker flag. Sometimes "undefined reference error" occur 
in wrong order of library option.
Adding '-v' option, one can  echo commands as they are executed.

>> mkoctfile -v PowerMeter.cc -L. -lusbdllnew

I do not see problems but I do not have enough knowledge to judge with 
confidence.

2. @n (n is number like @0) symbols problems for pexports.

https://sourceforge.net/p/mingw-w64/wiki2/gendef/
 However, unlike pexports, gendef scans and attempts to decode the dll file 
 to find out relevant details such as call convention used. It will try to 
 append the @n to symbols detected as using stdcall?.

Unfortunately gendef binary distributed with mingw-w64.

Download mingw-w64-v5.0.1.zip (source)

https://sourceforge.net/projects/mingw-w64/files/mingw-w64/mingw-w64-release/mingw-w64-v5.0.1.zip/download
 

Place mingw-w64-v5.0.1.zip at your preferable folder


Using windows explorer, copy "gendef" in folder "mingw-w64-tools" in 
mingw-w64-v5.0.1.zip in to another folder.

Start octave
>> system bash

bash-3.1$ cd "(path to 'gendef' folder )"
bash-3.1$ ./configure

bash-3.1$ make


After "make", gendef.exe is generated at (path to 'gendef' folder ) and copy it 
to appropriate place.  

gendef - xxx.dll 
(Do not forget '-' option to output console)
You can see the symbol generated by gendef.

gendef - xxx.dll > xxx.def

You can generate def file.

Tatsuro