idl compiler for CygWin

idl compiler for CygWin

[Monty Wiseman]

I posted this several hours ago to the .general list but it hasn't appeared
and there so I am cross posting here. Is there an ILD compiler for CygWin or
Linux I can download.

-Monty

Problems linking c++ class libraries

[Mark L. Wise]

Hello all!

I am relatively new to c++ and I have a question regarding linking class
libraries.

I have a "main line" program that calls a class out of a library (A) that I
built.  This class library also calls classes out of another library (B).
When I try to link I get an unresolved call to <the class name> class
(library B) that I call in library "A".

HOWEVER, If I include a "dummy" call in my "mainline" program to the class
in library "B", then the link from library "A" completes to library "B" and
the program runs.

Why do I have to include a reference call to the class in library "B" in my
mainline program to get it the linker to resolve the link?

Thanks in advance for any advice!!

Mark

Re: Problems linking c++ class libraries

[Ian Lance Taylor]

"Mark L. Wise" <mark@alpha2.com> writes:

> I am relatively new to c++ and I have a question regarding linking class
> libraries.
> 
> I have a "main line" program that calls a class out of a library (A) that I
> built.  This class library also calls classes out of another library (B).
> When I try to link I get an unresolved call to <the class name> class
> (library B) that I call in library "A".
> 
> HOWEVER, If I include a "dummy" call in my "mainline" program to the class
> in library "B", then the link from library "A" completes to library "B" and
> the program runs.
> 
> Why do I have to include a reference call to the class in library "B" in my
> mainline program to get it the linker to resolve the link?

Please don't send messages to this mailing list by replying to an
unrelated message.  It breaks threaded mail readers.  Thanks.

Your bug report is incomplete, because you don't say precisely what
you are doing, or what type of system you are using, or what version
of the compiler and linker you are using.

However, my guess is that you don't realize that the order in which
you mention libraries on the command line matters.  If library A
refers to library B, then you must list them in the order -lA -lB.

Ian

RE: Problems linking c++ class libraries

[Mark L. Wise]

Ian,

Thanks for the info.  It works great now!!!

Sorry about the broken thread...  I did not know.

Let me know if I can ever help you!!

Mark

-----Original Message-----
From: Ian Lance Taylor [mailto:ian@airs.com]
Sent: Sunday, August 24, 2003 6:20 PM
To: mark@alpha2.com
Cc: gcc-help@gcc.gnu.org
Subject: Re: Problems linking c++ class libraries


"Mark L. Wise" <mark@alpha2.com> writes:

> I am relatively new to c++ and I have a question regarding linking class
> libraries.
>
> I have a "main line" program that calls a class out of a library (A) that
I
> built.  This class library also calls classes out of another library (B).
> When I try to link I get an unresolved call to <the class name> class
> (library B) that I call in library "A".
>
> HOWEVER, If I include a "dummy" call in my "mainline" program to the class
> in library "B", then the link from library "A" completes to library "B"
and
> the program runs.
>
> Why do I have to include a reference call to the class in library "B" in
my
> mainline program to get it the linker to resolve the link?

Please don't send messages to this mailing list by replying to an
unrelated message.  It breaks threaded mail readers.  Thanks.

Your bug report is incomplete, because you don't say precisely what
you are doing, or what type of system you are using, or what version
of the compiler and linker you are using.

However, my guess is that you don't realize that the order in which
you mention libraries on the command line matters.  If library A
refers to library B, then you must list them in the order -lA -lB.

Ian