[vorbis-dev] new DLL additions in core libs

[Chris Wolf]

*********** REPLY SEPARATOR  ***********

On 9/13/2001 at 11:04 PM Brian Havard wrote:

>On Wed, 12 Sep 2001 19:57:10 -0700, Chris Wolf wrote:
>
>>On 9/13/2001 at 12:28 PM Brian Havard wrote:
>>
>>>On Wed, 12 Sep 2001 19:16:38 -0700, Chris Wolf wrote:
>>>
>>>>On 9/13/2001 at 11:55 AM Brian Havard wrote:
>>>>
>>>>>>
>>>>>>OK.  So the basic problem is that static externs are unsharable?  
>>>>>
>>>>>That doesn't sound right. It should work if (and only if) the variables
>>>are
>>>>>declared to the dll's user using __declspec(dllimport).
>>>>
>>>>I'm afraid that's not really true.  That is just an optimization.
>>>>To quote Microsoft's documentation:
>>>>
>>>>>You do not need to use _declspec(dllimport) for your code to compile
>>>>>correctly, but doing so allows the compiler to generate better code.
>The
>>>>>compiler is able to generate better code because it knows for sure
>>>whether
>>>>>a function exists in a DLL or not, so the compiler can produce codes
>that
>>>>>skip a level of indirection that would normally be present in a
>function
>>>>>call that crossed a DLL boundary. 
>>>
>>>That's not my experience. When porting a DLL of mine to Win32 I found
>that
>>>I was getting total garbage when accessing an array exported from it
>until
>>>I added the _declspec(dllimport). However, this was using Watcom C++, not
>>>VC. I'd still give it a try if I were you.
>>
>>That's definitely not the case here, because I also tried compiling
>vorbisenc.c 
>>into the main vorbis.dll, (one single DLL, no vorbisenc.dll) and the
>application ran fine.
>>
>>The problem is intra-DLL access, not DLL-application access, and yes, I
>tried
>>it anyway before I made the claim that it didn't work.  The problem is
>not garbage
>>upon dereferencing, the problem is an access violation upon an attempt to
>dereference.
>
>Ok, I was just hoping to save you some trouble if was the same problem I'd
>encountered as it took me a while to figure it out.

All right, thank you...   If you get a chance to do a build using Watcom C++, I would
appreciate any reports of your experience as well as build files, etc.

        -Chris

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