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

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

[boonflies]

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)`

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

[Jacob Sparre Andersen]

boonflies@gmail.com writes:

> We receive, undefined reference to `CLIENT_CR', while linking.

How did you do the linking then?  How does your project file look?  Or
the command line arguments to the compiler and/or linker?

Greetings,

Jacob
-- 
"Don't get me wrong, perl is an OK operating system, but it
 lacks a lightweight scripting language."

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

[Dennis Lee Bieber]

On Fri, 25 May 2018 06:52:09 -0700 (PDT), boonflies@gmail.com declaimed the
following:

>
>`void CLIENT_CR
>(
>    CREATE_INFO *  CreateInfo, 
>    ID         *  SessionId,
>    RESULT  *  Result 
>);`
>

	C prototype for a function...

>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");`
>

	Ada prototype and specification that it maps to a C function...

>3. In main.adb
>`#With TFTP;
>
>...
>TFTP.CLIENT_CR(INFO,ID,RESULT)`
>
	What's the # doing there?

	What you have not provided is:
a)	the actual C implementation of CLIENT_CR
b)	the link command that uses whatever file contains said C implementation


-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
	wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/ 

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

[Niklas Holsti]

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
       .      @       .