diff --git a/manual/PRESENTATION_Prog.tex b/manual/PRESENTATION_Prog.tex
index b0390cb99..f2791c571 100644
--- a/manual/PRESENTATION_Prog.tex
+++ b/manual/PRESENTATION_Prog.tex
@@ -550,7 +550,7 @@ by loading plugins into Yosys.
 \bigskip
 Use the following command to compile a Yosys plugin:
 \begin{lstlisting}[xleftmargin=1cm, basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont]
-yosys-config --exec --cxx --cxxflags --ldflags \
+yosys-config --exec --cxx --cxxflags -I../.. --ldflags \
              -o my_cmd.so -shared my_cmd.cc --ldlibs
 \end{lstlisting}
 
diff --git a/manual/PRESENTATION_Prog/Makefile b/manual/PRESENTATION_Prog/Makefile
index 2ac8e5bed..64ed1c583 100644
--- a/manual/PRESENTATION_Prog/Makefile
+++ b/manual/PRESENTATION_Prog/Makefile
@@ -5,7 +5,7 @@ CXXFLAGS=$(shell ../../yosys-config --cxxflags)
 DATDIR=$(shell ../../yosys-config --datdir)
 
 my_cmd.so: my_cmd.cc
-	../../yosys-config --exec --cxx $(subst $(DATDIR),../../share,$(CXXFLAGS)) --ldflags -o my_cmd.so -shared my_cmd.cc --ldlibs
+	../../yosys-config --exec --cxx $(subst $(DATDIR),../../share,$(CXXFLAGS)) -I../../ --ldflags -o my_cmd.so -shared my_cmd.cc --ldlibs
 
 test0.log: my_cmd.so
 	../../yosys -Ql test0.log_new -m ./my_cmd.so -p 'my_cmd foo bar' absval_ref.v