Re: undefined reference while calling an imported c function as procedure in ada

[Niklas Holsti <niklas.holsti@tidorum.invalid>]

On 18-05-25 16:52 , boonflies@gmail.com wrote:
> We receive, undefined reference to `CLIENT_CR', while linking.
>
> The code we are building
> In Tftp.h
>
> `void CLIENT_CR
> (
>     CREATE_INFO *  CreateInfo,
>     ID         *  SessionId,
>     RESULT  *  Result
> );`
>
> 2. In Tftp.ads
> `procedure CLIENT_CR( CreateInfo : in  Tpkg.CREATE_INFO;
>                               SessionId  : out Tpkg.ID;
>                              Result     : out RESULT );
>
>    pragma Import (C, CLIENT_CR, "CLIENT_CR");`
>
> 3. In main.adb
> `#With TFTP;
>
> ...
> TFTP.CLIENT_CR(INFO,ID,RESULT)`

Apply the "nm" tool to the object (.o) file compiled from Tftp.c 
(probably named Tftp.o) to see the link-name that the C (or C++?) 
compiler assigns to the CLIENT_CR subprogram. Use that link-name in the 
pragma Import.

Also, check that your linker command-line includes Tftp.o, or add a 
pragma Linker_Options naming that file to the Ada declaration.

-- 
Niklas Holsti
Tidorum Ltd
niklas holsti tidorum fi
       .      @       .