libavformat/dashenc.c: In function 'flush_init_segment':
libavformat/dashenc.c:601:49: warning: '%s' directive output may be truncated writing up to 1023 bytes into a region of size between 1 and 1024 [-Wformat-truncation=]
         snprintf(filename, sizeof(filename), '%s%s', c->dirname, os->initfile);
                                                 ^~
In file included from /usr/include/stdio.h:862:0,
                 from ./libavutil/common.h:38,
                 from ./libavutil/avutil.h:296,
                 from libavformat/dashenc.c:30:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:64:10: note: '__builtin___snprintf_chk' output between 1 and 2047 bytes into a destination of size 1024
   return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        __bos (__s), __fmt, __va_arg_pack ());
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
libavformat/dashenc.c: In function 'dash_init':
libavformat/dashenc.c:1592:49: warning: '%s' directive output may be truncated writing up to 1023 bytes into a region of size between 1 and 1024 [-Wformat-truncation=]
         snprintf(filename, sizeof(filename), '%s%s', c->dirname, os->initfile);
                                                 ^~
In file included from /usr/include/stdio.h:862:0,
                 from ./libavutil/common.h:38,
                 from ./libavutil/avutil.h:296,
                 from libavformat/dashenc.c:30:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:64:10: note: '__builtin___snprintf_chk' output between 1 and 2047 bytes into a destination of size 1024
   return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        __bos (__s), __fmt, __va_arg_pack ());
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
libavformat/dashenc.c: In function 'write_hls_media_playlist':
libavformat/dashenc.c:495:49: warning: 'media_' directive output may be truncated writing 6 bytes into a region of size between 1 and 1024 [-Wformat-truncation=]
         snprintf(playlist_name, string_size, '%smedia_%d.m3u8', base_url, id);
                                                 ^~~~~~
In file included from /usr/include/stdio.h:862:0,
                 from ./libavutil/common.h:38,
                 from ./libavutil/avutil.h:296,
                 from libavformat/dashenc.c:30:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:64:10: note: '__builtin___snprintf_chk' output between 13 and 1046 bytes into a destination of size 1024
   return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        __bos (__s), __fmt, __va_arg_pack ());
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
libavformat/dashenc.c: In function 'dash_flush':
libavformat/dashenc.c:1968:63: warning: '%s' directive output may be truncated writing up to 1023 bytes into a region of size between 1 and 1024 [-Wformat-truncation=]
             snprintf(os->full_path, sizeof(os->full_path), '%s%s', c->dirname, os->initfile);
                                                               ^~
In file included from /usr/include/stdio.h:862:0,
                 from ./libavutil/common.h:38,
                 from ./libavutil/avutil.h:296,
                 from libavformat/dashenc.c:30:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:64:10: note: '__builtin___snprintf_chk' output between 1 and 2047 bytes into a destination of size 1024
   return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        __bos (__s), __fmt, __va_arg_pack ());
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
libavformat/dashenc.c: In function 'dash_write_trailer':
libavformat/dashenc.c:495:49: warning: 'media_' directive output may be truncated writing 6 bytes into a region of size between 1 and 1024 [-Wformat-truncation=]
         snprintf(playlist_name, string_size, '%smedia_%d.m3u8', base_url, id);
                                                 ^~~~~~
libavformat/dashenc.c:495:46: note: directive argument in the range [0, 2147483647]
         snprintf(playlist_name, string_size, '%smedia_%d.m3u8', base_url, id);
                                              ^~~~~~~~~~~~~~~~~
In file included from /usr/include/stdio.h:862:0,
                 from ./libavutil/common.h:38,
                 from ./libavutil/avutil.h:296,
                 from libavformat/dashenc.c:30:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:64:10: note: '__builtin___snprintf_chk' output between 13 and 1045 bytes into a destination of size 1024
   return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        __bos (__s), __fmt, __va_arg_pack ());
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
libavformat/dashenc.c: In function 'dash_write_packet':
libavformat/dashenc.c:2265:59: warning: '%s' directive output may be truncated writing up to 1023 bytes into a region of size between 1 and 1024 [-Wformat-truncation=]
         snprintf(os->full_path, sizeof(os->full_path), '%s%s', c->dirname,
                                                           ^~
In file included from /usr/include/stdio.h:862:0,
                 from ./libavutil/common.h:38,
                 from ./libavutil/avutil.h:296,
                 from libavformat/dashenc.c:30:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:64:10: note: '__builtin___snprintf_chk' output between 1 and 2047 bytes into a destination of size 1024
   return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        __bos (__s), __fmt, __va_arg_pack ());
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
libavformat/mlvdec.c: In function 'read_header':
libavformat/mlvdec.c:361:63: warning: '__builtin___snprintf_chk' output may be truncated before the last format character [-Wformat-truncation=]
             snprintf(filename + strlen(filename) - 2, 3, '%02d', i);
                                                               ^
In file included from /usr/include/stdio.h:862:0,
                 from libavformat/avformat.h:322,
                 from libavformat/mlvdec.c:30:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:64:10: note: '__builtin___snprintf_chk' output between 3 and 4 bytes into a destination of size 3
   return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        __bos (__s), __fmt, __va_arg_pack ());
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
libavformat/matroskaenc.c: In function 'mkv_write_trailer':
libavformat/matroskaenc.c:3183:58: warning: '%012.9f' directive output may be truncated writing between 12 and 320 bytes into a region of size between 8 and 14 [-Wformat-truncation=]
                 snprintf(duration_string, 20, '%02d:%02d:%012.9f',
                                                          ^~~~~~~
In file included from /usr/include/stdio.h:862:0,
                 from libavformat/avio.h:30,
                 from libavformat/av1.h:26,
                 from libavformat/matroskaenc.c:26:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:64:10: note: '__builtin___snprintf_chk' output between 19 and 333 bytes into a destination of size 20
   return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        __bos (__s), __fmt, __va_arg_pack ());
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
libavformat/mpegenc.c: In function 'mpeg_mux_init':
libavformat/mpegenc.c:432:13: error: a label can only be part of a statement and a declaration is not a statement
             AVPacketSideData *sd;
             ^~~~~~~~~~~~~~~~
libavformat/mpegenc.c:433:13: error: expected expression before 'AVCPBProperties'
             AVCPBProperties *props = NULL;
             ^~~~~~~~~~~~~~~
libavformat/mpegenc.c:441:17: error: 'props' undeclared (first use in this function)
                 props = (AVCPBProperties*)sd->data;
                 ^~~~~
libavformat/mpegenc.c:441:17: note: each undeclared identifier is reported only once for each function it appears in
make: *** [libavformat/mpegenc.o] Error 1
make: *** Waiting for unfinished jobs....
libavformat/movenc.c: In function 'mov_flush_fragment':
libavformat/movenc.c:1127:8: warning: assuming signed overflow does not occur when assuming that (X - c) > X is always false [-Wstrict-overflow]
     if (cluster_idx >= track->entry)
        ^