[Ffmpeg-devel] Win32 unresolved external symbol

Michel Bardiaux mbardiaux
Thu Sep 1 11:51:58 CEST 2005

Martin Boehme wrote:
> Michel Bardiaux wrote:
> [on the subject of linking static FFmpeg libs compiled with MinGW into 
> an MSVC app]
>> You have to add libgcc.a to the build (mine is in 
>> C:\MinGW\lib\gcc-lib\mingw32\3.2)
> Is this really safe? I seem to remember there was a discussion about 
> this a while back, and the conclusion was that while linking to libgcc.a 
> works, it is a Bad Thing in some way or another, and that the libgcc.a 
> runtime doesn't play well in an MSVC environment... 

Its only a very small part of the gcc runtime, the one containing 
functions called because the call is generated by the compiler for some 
kinds of math operations on types not supported by the hardware.

> IIRC, the gist was 
> that there was no good way to link a MinGW compiled static lib into an 
> MSVC app and the only "clean" solution is link against DLLs.

Good call, the OP did not actually specify whether he linked against 
static or DLL.

> All of this is "IIRC" -- can someone jump in to clarify? I don't want to 
> start any rumours here... from all I know, the libgcc.a solution may be 
> completely safe...

And if its not and MSVC support is required, then --enable-shared should 
be mandatory. OK?

> Martin

Michel Bardiaux
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