llvm dev - Mar 2012 - [LLVMdev] Linking problem in a pass

My pass uses another class which is defined in a separate .h file, which
sits in the same folder as the pass .cpp file. The pass compiles fine, but
when using the pass "opt -load ...", there is an error: opt symbol
lookup
error  .... undefined symbol xxx,  where xxx is the class name. It looks
like that class file's object file is not linked into the pass.so file. How
should I change the Makefile to make the linking happen?

Thanks,
Welson
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20120229/fcb2b0ec/attachment.html>

On 2/29/12 11:03 PM, Welson Sun wrote:
> My pass uses another class which is defined in a separate .h file, 
> which sits in the same folder as the pass .cpp file. The pass compiles 
> fine, but when using the pass "opt -load ...", there is an error:
opt
> symbol lookup error  .... undefined symbol xxx,  where xxx is the 
> class name. It looks like that class file's object file is not linked 
> into the pass.so file. How should I change the Makefile to make the 
> linking happen?
If your .cpp file isn't including the .h file, then the class in the .h 
file isn't being compiled and, therefore, isn't being included in the 
final library file.

Classes should be declared in header files and have their methods 
defined in .cpp files.  That's the easiest way to fix the problem.

-- John T.
>
> Thanks,
> Welson
>
>
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20120301/8c50422f/attachment.html>

Originally, the problem is the lack of .cpp file. Then I noticed the
compilation log is not showing the .o file being generated for the non-pass
classes.

Then I added the .cpp files for each .h file, then the .o files are being
generated, shown in the Debug directory. Actually, if I add "VERBOSE =
1"
in the Makefile, it shows the linking command is actually linking all the
.o files into the pass.so file.

Any help will be appreciated.

Thanks!
Welson


On Thu, Mar 1, 2012 at 6:45 AM, John Criswell <criswell at illinois.edu>
wrote:
>  On 2/29/12 11:03 PM, Welson Sun wrote:
>
> My pass uses another class which is defined in a separate .h file, which
> sits in the same folder as the pass .cpp file. The pass compiles fine, but
> when using the pass "opt -load ...", there is an error: opt
symbol lookup
> error  .... undefined symbol xxx,  where xxx is the class name. It looks
> like that class file's object file is not linked into the pass.so file.
How
> should I change the Makefile to make the linking happen?
>
>
> If your .cpp file isn't including the .h file, then the class in the .h
> file isn't being compiled and, therefore, isn't being included in
the final
> library file.
>
> Classes should be declared in header files and have their methods defined
> in .cpp files.  That's the easiest way to fix the problem.
>
> -- John T.
>
>
>
>  Thanks,
> Welson
>
>
> _______________________________________________
> LLVM Developers mailing listLLVMdev at cs.uiuc.edu        
http://llvm.cs.uiuc.eduhttp://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>
>
>
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>
>

-- 
Welson

Phone: (408) 418-8385
Email:  welson.sun at gmail.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20120301/8a858e1a/attachment.html>