sortie@sortie-pc1 ~/gnash $ ./configure --prefix=/usr --enable-media=ffmpeg --enable-renderer=opengl --enable-hwaccel=vaapi --enable-docbook
checking build system type... x86_64-unknown-linux-gnu
checking host system type... x86_64-unknown-linux-gnu
checking for g++... g++
# ...
config.status: executing po-directories commands
config.status: executing libtool commands

Configurable options are:
        POSIX Threads support enabled (default)
        NPAPI plugin enabled (default). Use --disable-npapi to disable.
            NPAPI plugin will be installed in /home/sortie/.mozilla/plugins
        KPARTS 3.x plugin disabled.
        KPARTS 4.x plugin disabled.
Configured paths for x86_64-unknown-linux-gnu are:
        QT4 flags are: -I/usr/include/qt4 -I/usr/include/qt4/QtOpenGL -I/usr/include/qt4/QtCore -I/usr/include/qt4/QtGui
        QT4 libs are: -lQtGui -lQtCore
        JPEG flags are: default include path
        JPEG libs are: -L/usr/lib32 -ljpeg
        GIF flags are: default include path
        GIF libs are: -lgif
        PNG flags are: -I/usr/include/libpng12
        PNG libs are: -L/usr/lib/x86_64-linux-gnu -lpng12
        OpenGL flags are: default include path
        OpenGL libs are: -lGL -lGLU
        GtkGLExt flags are: -pthread -I/usr/include/pango-1.0 -I/usr/include/gio-unix-2.0/ -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/freetype2 -I/usr/include/libpng12 -I/usr/include/atk-1.0 -I/usr/include/gtkglext-1.0 -I/usr/lib/gtkglext-1.0/include -I/usr/include/gtk-2.0 -I/usr/lib/gtk-2.0/include -I/usr/include/cairo -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/pixman-1
        GtkGLExt libs are: -lgtkglext-x11-1.0 -lgdkglext-x11-1.0 -lGLU -lGL -lXmu -lXt -lSM -lICE -lgtk-x11-2.0 -lpangox-1.0 -lX11 -lgdk-x11-2.0 -latk-1.0 -lgio-2.0 -lpangoft2-1.0 -lpangocairo-1.0 -lgdk_pixbuf-2.0 -lm -lcairo -lpango-1.0 -lfreetype -lfontconfig -lgobject-2.0 -lgmodule-2.0 -lgthread-2.0 -lrt -lglib-2.0
        GTK2 flags are: -pthread -I/usr/include/atk-1.0 -I/usr/include/pango-1.0 -I/usr/include/gio-unix-2.0/ -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/freetype2 -I/usr/include/libpng12 -I/usr/include/gtk-2.0 -I/usr/lib/gtk-2.0/include -I/usr/include/cairo -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/pixman-1
        GTK2 libs are: -lgtk-x11-2.0 -lgdk-x11-2.0 -latk-1.0 -lgio-2.0 -lpangoft2-1.0 -lpangocairo-1.0 -lgdk_pixbuf-2.0 -lm -lcairo -lpango-1.0 -lfreetype -lfontconfig -lgobject-2.0 -lgmodule-2.0 -lgthread-2.0 -lrt -lglib-2.0
        Pango flags are: -pthread -I/usr/include/pango-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include
        Pango libs are: -lpangox-1.0 -lX11 -lpango-1.0 -lgobject-2.0 -lgmodule-2.0 -lgthread-2.0 -lrt -lglib-2.0
        GLib flags are: -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include   -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include
        GLib libs are: -L/usr/lib/x86_64-linux-gnu -lglib-2.0
        ATK flags are: -pthread -I/usr/include/atk-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include
        ATK libs are: -pthread -L/usr/lib/x86_64-linux-gnu -latk-1.0 -lgobject-2.0 -lgthread-2.0 -lrt -lglib-2.0
        MP3 and video support enabled through FFmpeg
        FFmpeg flags are: -D__STDC_CONSTANT_MACROS -I/usr/include/libavcodec
        FFmpeg libs are:  -lavcodec   -lavformat   -lavutil    -lswscale
        SDL flags are: -I/usr/include/SDL -D_GNU_SOURCE=1 -D_REENTRANT
        SDL libs are:  -lSDL
        POSIX Threads flags are: -pthread
        POSIX Threads lib is: -L/usr/lib/x86_64-linux-gnu -lpthread
        You have version 0.8.8 of the DocBook2X tools.
        CURL flags are:  -DCURL_STATICLIB
        CURL libs are: -lcurl
        Speex flags are:
        Speex libs are: -lspeex
        Speex DSP flags are:
        Speex DSP libs are: -lspeexdsp
        BOOST flags are:
        BOOST libs are: -L/usr/lib64 -lboost_thread-mt -lboost_program_options-mt
        BOOST libs for cygnal are:  -lboost_serialization-mt -lboost_date_time-mt
        MING flags are -I/usr/include
        MING libs are -L/usr/lib -lz -lm -lungif -lpng -lming
        MING version code is 00040300
        MAKESWF is /usr/bin/makeswf
        MTASC is /usr/bin/mtasc
        MTASC CLASSPATH is /usr/share/mtasc/std
        HAXE is /usr/bin/haxe
        HAXE CLASSPATH is /usr/share/haxe/
        SWFMILL is /usr/bin/swfmill
        PERL is /usr/bin/perl
        Z flags are: default include path
        Z libs are: -L/usr/lib/x86_64-linux-gnu -lz
        FreeType flags are: -I/usr/include/freetype2
        FreeType libs are: -L/usr/lib/x86_64-linux-gnu -lfreetype
        Fontconfig flags are:
        Fontconfig libs are: -L/usr/lib/x86_64-linux-gnu -lfontconfig
        LIBVA flags are:
        LIBVA libraries are: -lva
        LIBVA X11 flags are:
        LIBVA X11 libraries are: -lva-x11 -lva
        LIBVA GLX flags are:
        LIBVA GLX libraries are: -lva-glx -lva
        NPAPI flags are: -I/usr/include/xulrunner-2.0 -DXP_UNIX
        DEJAGNU's runtest is /usr/bin/runtest
        LIBLTDL flags are:
        LIBLTDL libs are: -lltdl
        Only building these ActionScript classes into the library:

        You have netcat installed, which is only used for testing
        You have wget installed, which is only used for testing
--------
        Building Cygnal media server disabled.
        Top level for cross compiling support files is:
        Enabling security features:  localconnection
        Enabling hardware acceleration features: VAAPI
        Enabling statistics collecting for:  cache
        GUI toolkits supported: qt4,gtk,sdl
        Renderers supported:  opengl
        Hardware Acceleration: VAAPI
        Media handlers: ffmpeg
        Using sdl for sound handling
        Using  mode for shared memory
        DocBook document processing enabled (for "make html" and "make pdf")
        Docbook styles sheets in /usr/share/xml/docbook/stylesheet/nwalsh

        WARNING: You need to have 'swfc' from SWFTools installed
                 to run some of the tests in Gnash testsuite.
                 You can install it from http://www.swftools.org/
                 or .deb users: apt-get install swftools
                 or .rpm users: yum install swftools
        WARNING: you need as3compile from SWFTools
                 to run some of the tests in Gnash testsuite.
                 You can install it from http://www.swftools.org/

Gnash should still compile even with these warnings.
If it doesn't, report the warnings as a bug.

.deb users might be able to install most dependencies by executing:
sudo ./deb-attempt-install-dependencies.sh

sortie@sortie-pc1 ~/gnash $