demuxers: report failed checks

diff --git a/src/demuxers/mod.rs b/src/demuxers/mod.rs
index 46603b23433361c7e5aa0a839f9fa72ad0222c12..3ecc983f7a75482a2bf16393a918bc2ee9f0a58a 100644 (file)
--- a/src/demuxers/mod.rs
+++ b/src/demuxers/mod.rs
@@ -201,7 +201,7 @@ pub trait DemuxerCreator {
 }
 
 macro_rules! validate {
-    ($a:expr) => { if !$a { return Err(DemuxerError::InvalidData); } };
+    ($a:expr) => { if !$a { println!("check failed at {}:{}", file!(), line!()); return Err(DemuxerError::InvalidData); } };
 }
 
 #[cfg(feature="demuxer_gdv")]