fixed some typecasting issues with modern c++ compilers.

version raised to 0.9.1

samples/app/Makefile.in

@@ -1,7 +1,7 @@
-# Makefile.in generated by automake 1.16.2 from Makefile.am.
+# Makefile.in generated by automake 1.16.5 from Makefile.am.
 # @configure_input@
 
-# Copyright (C) 1994-2020 Free Software Foundation, Inc.
+# Copyright (C) 1994-2021 Free Software Foundation, Inc.
 
 # This Makefile.in is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -203,8 +203,6 @@ am__define_uniq_tagged_files = \
   unique=`for i in $$list; do \
     if test -f "$$i"; then echo $$i; else echo $(srcdir)/$$i; fi; \
   done | $(am__uniquify_input)`
-ETAGS = etags
-CTAGS = ctags
 am__DIST_COMMON = $(srcdir)/Makefile.in $(top_srcdir)/ac/depcomp
 DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST)
 ACLOCAL = @ACLOCAL@
@@ -221,6 +219,8 @@ CCDEPMODE = @CCDEPMODE@
 CFLAGS = @CFLAGS@
 CPP = @CPP@
 CPPFLAGS = @CPPFLAGS@
+CSCOPE = @CSCOPE@
+CTAGS = @CTAGS@
 CXX = @CXX@
 CXXCPP = @CXXCPP@
 CXXDEPMODE = @CXXDEPMODE@
@@ -237,6 +237,7 @@ ECHO_C = @ECHO_C@
 ECHO_N = @ECHO_N@
 ECHO_T = @ECHO_T@
 EGREP = @EGREP@
+ETAGS = @ETAGS@
 EXEEXT = @EXEEXT@
 FGREP = @FGREP@
 GREP = @GREP@
@@ -552,7 +553,6 @@ cscopelist-am: $(am__tagged_files)
 
 distclean-tags:
 	-rm -f TAGS ID GTAGS GRTAGS GSYMS GPATH tags
-
 distdir: $(BUILT_SOURCES)
 	$(MAKE) $(AM_MAKEFLAGS) distdir-am