Merge 76138 - Properly account the thread index on all exit paths from the fu...

source/patched-ffmpeg-mt/libavcodec/pthread.c

Index: source/patched-ffmpeg-mt/libavcodec/pthread.c
===================================================================
--- source/patched-ffmpeg-mt/libavcodec/pthread.c	(revision 76144)
+++ source/patched-ffmpeg-mt/libavcodec/pthread.c	(working copy)
@@ -448,9 +448,11 @@
     if (err) return err;
 
     fctx->next_decoding++;
+    int decoding_save = fctx->next_decoding;
+    if (fctx->next_decoding >= thread_count) fctx->next_decoding = 0;
 
     if (fctx->delaying && avpkt->size) {
-        if (fctx->next_decoding >= (thread_count-1)) fctx->delaying = 0;
+        if (decoding_save >= (thread_count-1)) fctx->delaying = 0;
 
         *got_picture_ptr=0;
         return 0;
@@ -479,7 +481,6 @@
 
     update_thread_context_from_copy(avctx, p->avctx, 1);
 
-    if (fctx->next_decoding >= thread_count) fctx->next_decoding = 0;
     fctx->next_finished = returning_thread;
 
     return p->result;