doc/concepts.tex: Fix cross-reference to compatibility section.

diff --git a/doc/concepts.tex b/doc/concepts.tex
index c729490..5cb57bc 100644 (file)
--- a/doc/concepts.tex
+++ b/doc/concepts.tex
@@ -271,7 +271,7 @@ slots.  If you want to hide implementation details, the best approach is to
 stash them in a dynamically allocated private structure, and leave a pointer
 to it in a slot.  (This will also help preserve binary compatibility, because
 the private structure can grow more members as needed.  See
-\xref{sec:fixme.compatibility} for more details.)
+\xref{sec:concepts.compatibility} for more details.)
 
 
 \subsubsection{Vtables}