Dear all,
as usual it's a crazy mission to compile gnuplot on osx...
Since it seems that it's a problem for many, here s my experience.

I have installed a lot of libraries (pdflib, gdlib etc..) via fink

Now, the last thing (I suppose introduced via Snow Leopard) is that we
have to dd the architechure flag, so to compile, I have to configure
like this:

LDFLAGS=3D"-L/sw/lib -arch i386" CFLAGS=3D"-arch i386" ./configure --
prefix=3D/sw --disable-wxwidgets
note that the first -L/sw/lib is just to force gnuplot to use the real
fink readline and not the prebuilt one.

I had to remove the wxwidget because if I use the same configure line
enabling them:

LDFLAGS=3D"-L/sw/lib -arch i386" CFLAGS=3D"-arch i386" ./configure --
prefix=3D/sw

I get this error

[...]
g++ -DHAVE_CONFIG_H -I. -I..  -I../term -I../term -DBINDIR=3D\"/sw/bin\"
-DX11_DRIVER_DIR=3D\"/sw/libexec/gnuplot/4.5\" -DGNUPLOT_PS_DIR=3D\"/sw/
share/gnuplot/4.5/PostScript\" -DGNUPLOT_JS_DIR=3D\"/sw/share/gnuplot/
4.5/js\" -DCONTACT=3D\"gnuplot-bugs@lists.sourceforge.net\" -DHELPFILE=3D
\"/sw/share/gnuplot/4.5/gnuplot.gih\" -DGNUPLOT_X11=3D\"`echo
gnuplot_x11 | sed 's,x,x,'`\"  -I/sw/include -I/sw/include -I/sw/
include/cairo -I/sw/include/pixman-1 -I/sw/include/freetype2 -I/sw/
include -I/sw/include/libpng12 -I/sw/include/pango-1.0 -I/sw/include/
glib-2.0 -I/sw/lib/glib-2.0/include -I/usr/X11R6/include -I/usr/X11/
include -I/sw/include/cairo -I/sw/include/pixman-1 -I/sw/include/
freetype2 -I/sw/include -I/sw/include/libpng12 -I/sw/include/pango-1.0
-I/sw/include/glib-2.0 -I/sw/lib/glib-2.0/include -I/usr/X11R6/include
-I/usr/X11/include  -arch i386 -I/sw/lib/wx/include/gtk2-unicode-
release-2.8 -I/sw/include/wx-2.8 -D_FILE_OFFSET_BITS=3D64 -D_LARGE_FILES
-D__WXGTK__ -fno-rtti  -I/sw/include/cairo -I/sw/include/pixman-1 -I/
sw/include/freetype2 -I/sw/include -I/sw/include/libpng12 -I/sw/
include/pango-1.0 -I/sw/include/glib-2.0 -I/sw/lib/glib-2.0/include -I/
usr/X11R6/include -I/usr/X11/include -I/sw/include/gtk-2.0 -I/sw/lib/
gtk-2.0/include -I/sw/include/atk-1.0 -I/sw/include/cairo -I/sw/
include/pango-1.0 -I/sw/include/glib-2.0 -I/sw/lib/glib-2.0/include -I/
sw/include/pixman-1 -I/sw/include/freetype2 -I/sw/include -I/sw/
include/libpng12 -I/usr/X11R6/include -I/usr/X11/include -MT wxt_gui.o
-MD -MP -MF .deps/wxt_gui.Tpo -c -o wxt_gui.o `test -f 'wxterminal/
wxt_gui.cpp' || echo './'`wxterminal/wxt_gui.cpp
wxterminal/wxt_gui.cpp: In function =91void wxt_init()=92:
wxterminal/wxt_gui.cpp:1490: error: =91dynamic_cast=92 not permitted with -
fno-rtti
wxterminal/wxt_gui.cpp: In function =91void wxt_atexit()=92:
wxterminal/wxt_gui.cpp:3196: error: =91dynamic_cast=92 not permitted with -
fno-rtti
make[3]: *** [wxt_gui.o] Error 1
make[2]: *** [all-recursive] Error 1
make[1]: *** [all-recursive] Error 1
make: *** [all] Error 2

I am using the gcc version
i686-apple-darwin10-g++-4.2.1 (GCC) 4.2.1 (Apple Inc. build 5646)
Copyright (C) 2007 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There
is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE.

Any hints?

Many thanks, I hope this helps someone