From 42daa20056545c36983cb0ab8edcfdda3ebf9ebe Mon Sep 17 00:00:00 2001
From: "FeRD (Frank Dana)" <ferdnyc@gmail.com>
Date: Mon, 4 Nov 2019 03:33:19 -0500
Subject: [PATCH] FindFFmpeg: Expand duplicate-removal

Repeated invocations (e.g. `cmake .` in an already-configured dir) might
cause variables to collect duplicates.
---
 cmake/Modules/FindFFmpeg.cmake | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/cmake/Modules/FindFFmpeg.cmake b/cmake/Modules/FindFFmpeg.cmake
index b2409e05..b6da9244 100644
--- a/cmake/Modules/FindFFmpeg.cmake
+++ b/cmake/Modules/FindFFmpeg.cmake
@@ -180,9 +180,16 @@ foreach (_component ${FFmpeg_FIND_COMPONENTS})
   endif ()
 endforeach ()
 
-# Build the include path with duplicates removed.
+# Build the result lists with duplicates removed, in case of repeated
+# invocations.
 if (FFmpeg_INCLUDE_DIRS)
   list(REMOVE_DUPLICATES FFmpeg_INCLUDE_DIRS)
+endif()
+if (FFmpeg_LIBRARIES)
+  list(REMOVE_DUPLICATES FFmpeg_LIBRARIES)
+endif()
+if(FFmpeg_DEFINITIONS)
+  list(REMOVE_DUPLICATES FFmpeg_DEFINITIONS)
 endif ()
 
 # cache the vars.