Re: d3dx9.lib is not managed by ld, but libd3dx9.a is

[Roumen Petrov]

Vincent Torri wrote:
> Hey,
>
> I'm writing a dll using D3D and autotools stuff (MSYS / MinGW). I pass 
> -ld3dx9 and i have added everything so that the dll is built.
>
> If I add from the DirectX SDK d3dx9.lib in /mingw/lib, i have the usual 
> warning message from linker / libtool:
>
> *** Warning: linker path does not have real file for library -ld3dx9. 
> blah blah blah
>
> and only the static lib is built.
>
> If I rename d3dx9.lib to libd3dx9.a, then the DLL is built. I don't 
> understand why because, according to the doc of ld for win32:
>
> http://sourceware.org/binutils/docs/ld/WIN32.html
>
> if I pass -ld3dx9, then d3dx9.lib should be used.
>
> What is the reason of the failure ?
>
> thank you
>
> Vincent Torri

I'm not sure that libtool has to deal with library '.lib' suffix. From 
the suffix is not clear type of library file - static or import library.
GNU compiler(mingw) use suffix '.a'  for static library and '.dll.a' for 
import libraries.
If a xx.lib file is found in search path libtool has to process file and 
to find its type(static/import). This impact performance.

Also support for MSVC import libraries isn't perfect and linker will 
fail to link if a library export variables. Note in this case GNU linker 
succeed to link directly shared(DLL) library.

Roumen