doc/general.texi: add note about 32-bit GCC builds of AviSynth+

[ffmpeg] / doc / general.texi

diff --git a/doc/general.texi b/doc/general.texi
index 109c8c58cc2594f831658a1f69fd75dab892e249..d2324612c2c6435c9bb206b4cb8720ad9b2abcbc 100644 (file)
--- a/doc/general.texi
+++ b/doc/general.texi
@@ -46,22 +46,24 @@ without needing to search for these headers themselves.
 
 For Windows, supported AviSynth variants are
 @url{http://avisynth.nl, AviSynth 2.6 RC1 or higher} for 32-bit builds and
-@url{http://avs-plus.net, AviSynth+ r1718 or higher} for 32-bit and 64-bit builds.
+@url{http://avisynth.nl/index.php/AviSynth+, AviSynth+ r1718 or higher} for 32-bit and 64-bit builds.
 
 For Linux and OS X, the supported AviSynth variant is
 @url{https://github.com/avxsynth/avxsynth, AvxSynth}.
 
 @float NOTE
-There is currently a regression in AviSynth+'s @code{capi.h} header as of
-October 2016, which interferes with the ability for builds of FFmpeg to use
-MSVC-built binaries of AviSynth. Until this is resolved, you can make sure
-a known good version is installed by checking out a version from before
-the regression occurred:
-
-@code{git clone -b MT git://github.com/AviSynth/AviSynthPlus.git @*
-cd AviSynthPlus @*
-git checkout -b oldheader b4f292b4dbfad149697fb65c6a037bb3810813f9 @*
-make install PREFIX=/install/prefix}
+In 2016, AviSynth+ added support for building with GCC. However, due to
+the eccentricities of Windows' calling conventions, 32-bit GCC builds
+of AviSynth+ are not compatible with typical 32-bit builds of FFmpeg.
+
+By default, FFmpeg assumes compatibility with 32-bit MSVC builds of
+AviSynth+ since that is the most widely-used and entrenched build
+configuration.  Users can override this and enable support for 32-bit
+GCC builds of AviSynth+ by passing @code{-DAVSC_WIN32_GCC32} to
+@code{--extra-cflags} when configuring FFmpeg.
+
+64-bit builds of FFmpeg are not affected, and can use either MSVC or
+GCC builds of AviSynth+ without any special flags.
 @end float
 
 @float NOTE