diff --git a/include/armadillo_bits/subview_meat.hpp b/include/armadillo_bits/subview_meat.hpp
index e7439171..0e20d39d 100644
--- a/include/armadillo_bits/subview_meat.hpp
+++ b/include/armadillo_bits/subview_meat.hpp
@@ -1485,6 +1485,8 @@ subview<eT>::is_finite() const
   {
   arma_extra_debug_sigprint();
   
+  if(arma_config::fast_math)  { arma_debug_warn_level(2, "is_finite(): detection of non-finite values is not reliable in fast math mode"); }
+  
   const uword local_n_rows = n_rows;
   const uword local_n_cols = n_cols;