avfilter/vf_stack: Don't modify const strings
authorAndreas Rheinhardt <andreas.rheinhardt@gmail.com>
Tue, 14 May 2019 04:15:17 +0000 (06:15 +0200)
committerPaul B Mahol <onemda@gmail.com>
Tue, 14 May 2019 12:47:51 +0000 (14:47 +0200)
commit670251de56cdcda0c32d588959c8ed2da09075a2
tree8590795298401f1ac80c04ce00ca4518318ce0b5
parent8ef163ba9e3d2d7cb31856c33f86439e234fe623
avfilter/vf_stack: Don't modify const strings

b3b7ba62 introduced undefined behaviour: A (non-modifiable) string
literal has been assigned to a modifiable string; said string was indeed
modified later via av_strtok.
This of course caused compiler warnings because of the discarded
qualifier; these are in particular fixed by this commit.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
libavfilter/vf_stack.c