I'm not sure if vis is supported in suckless mailing list, but as it was discussed here previously, i'm writing here.
There are two issues with buffer_alloc function(s). First function is located in buffer.c: http://repo.or.cz/w/vis.git/blob/HEAD:/buffer.c The problem is on line 15: http://repo.or.cz/w/vis.git/blob/HEAD:/buffer.c#l15 If realloc fails, buf->data is set to NULL, but original buf->data is not freed, see realloc(3). The result of realloc should be stored in separate variable and buffer_free should be called to free buf->data and set size and len to 0 if realloc fails. Another issue is that there is another buffer_alloc in text.c: http://repo.or.cz/w/vis.git/blob/HEAD:/text.c Maybe these functions and data structures should be renamed to avoid name conflict.
