--- a/Makefile.am
+++ b/Makefile.am
@@ -193,7 +193,7 @@
 endif
 
 # We look at a sndfile symbol when libquickplot runs
-libquickplot_la_LIBADD = $(sndfile_LIBS)
+libquickplot_la_LIBADD = $(sndfile_LIBS) -lm
 
 if QP_DEBUG
 libquickplot_la_SOURCES += debug_spew.c
@@ -336,8 +336,8 @@
 if HAVE_LOCAL_SCREENSHOTS
 
 install-exec-hook:
-	mkdir -p $(htmldir)
-	cp ScreenShot_* _ScreenShot_* $(htmldir)
+	mkdir -p $(DESTDIR)$(htmldir)
+	cp ScreenShot_* _ScreenShot_* $(DESTDIR)$(htmldir)
 
 thumbs.htm: mk_thumbs.htm.bash
 	./mk_thumbs.htm.bash > $@