1 files changed, 2 insertions, 0 deletions
diff --git a/src/aig/int/intCtrex.c b/src/aig/int/intCtrex.c
index 98c01de6..c0bbec1c 100644
--- a/src/aig/int/intCtrex.c
+++ b/src/aig/int/intCtrex.c
@@ -111,6 +111,8 @@ void * Inter_ManGetCounterExample( Aig_Man_t * pAig, int nFrames, int fVerbose )
     Cnf_DataFree( pCnf );
     if ( pSat == NULL )
     {
+        printf( "Counter-example generation in command \"int\" has failed.\n" );
+        printf( "Use command \"bmc2\" to produce a valid counter-example.\n" );
         Vec_IntFree( vCiIds );
         return NULL;
     }