Bugzilla Bug 121372

dosbox has support for an internal debugger which can be enabled with
--enable-debug and --enable-debug=heavy respectively, the latter enabling even
more debug options. Respecting both probably doesn't make much sense since
those who want the debugger want 'heavy' anyways - and those who don't,
neither. See attached ebuild patch.

Created an attachment (id=78765) [edit]
dosbox-enable-debugger.patch

ebuild diff

I've created a new patch for dosbox-0.70

dependency to libpng is optional - only needed for screenshots
dependency to zlib is gone - only needed for libpng and pulled by
media-libs/libpng
new dependency to ncurses - when debug useflag is used
dependency to sdl-sound|net is optional - only needed for ipx network/cdrom
sound stuff




 inherit games

@@ -11,15 +11,15 @@
 KEYWORDS="amd64 ppc ~sparc x86"
 LICENSE="GPL-2"
 SLOT="0"
-IUSE="alsa hardened opengl"
+IUSE="alsa debug hardened opengl sdl png"

-DEPEND="sys-libs/zlib
-       alsa? ( media-libs/alsa-lib )
+DEPEND="alsa? ( media-libs/alsa-lib )
        opengl? ( virtual/opengl )
-       media-libs/libpng
+       png? ( media-libs/libpng )
+       debug? ( sys-libs/ncurses )
        >=media-libs/libsdl-1.2.0
-       media-libs/sdl-net
-       media-libs/sdl-sound"
+       sdl? ( media-libs/sdl-net
+               media-libs/sdl-sound )"

 src_compile() {
        local myconf=
@@ -31,6 +31,9 @@
        if use hardened ; then
                myconf="${myconf} --disable-dynamic-x86"
        fi
+       if use debug ; then
+               myconf="${myconf} --enable-debug"
+       fi
        egamesconf \
                --disable-dependency-tracking \
                ${myconf} \

(From update of attachment 78765 [edit])
No likey the first patch.  I like the second, but throw me a bone and attach it
as text/plain please.

Created an attachment (id=112723) [edit]
patch to enable --debug and to fix various optional dependencies

here you go

in portage.  thanks for the patch.