error compiling gnome-mag: warning: implicit declaration of function `round'

[Carlos Eduardo Rodrigues Diógenes <cerdiogenes yahoo com br>]

Hi,

I'm making some modifications in the gnome-mag code and I haved to use
the round () function, but when I try to compile I get the following
warning:

warning: implicit declaration of function `round'

I don't know why the function round is implicit declarated, since I'm
including the math.h file. Someone can give me any help.

This is the entirely output of my compilation:

make  all-am
make[1]: Entering directory `/home/kadu/gnome-mag/unstable/magnifier'
if gcc -DHAVE_CONFIG_H -I. -I. -I.. -I /usr/include -DORBIT2=1 -pthread
-I/usr/include/at-spi-1.0 -I/usr/include/libbonobo-2.0
-I/usr/include/atk-1.0 -I/usr/include/gtk-2.0 -I/usr/include/glib-2.0
-I/usr/lib/glib-2.0/include -I/usr/include/orbit-2.0
-I/usr/include/bonobo-activation-2.0 -I/usr/lib/gtk-2.0/include
-I/usr/include/cairo -I/usr/include/pango-1.0   -I.. -I.. -I../idl
-DG_DISABLE_DEPRECATED -DGDK_DISABLE_DEPRECATED
-DGDK_PIXBUF_DISABLE_DEPRECATED -DGTK_DISABLE_DEPRECATED
-DGNOME_DISABLE_DEPRECATED -DCURSORSDIR=\""/usr/share/gnome-mag"\"
-I /usr/include -I /usr/include -g -O2 -Wall -I /usr/include -DORBIT2=1
-pthread -I/usr/include/at-spi-1.0 -I/usr/include/libbonobo-2.0
-I/usr/include/atk-1.0 -I/usr/include/gtk-2.0 -I/usr/include/glib-2.0
-I/usr/lib/glib-2.0/include -I/usr/include/orbit-2.0
-I/usr/include/bonobo-activation-2.0 -I/usr/lib/gtk-2.0/include
-I/usr/include/cairo -I/usr/include/pango-1.0   -I /usr/include
-I /usr/include -g -O2 -Wall -MT magnifier-zoom-region.o -MD -MP -MF
".deps/magnifier-zoom-region.Tpo" -c -o magnifier-zoom-region.o `test -f
'zoom-region.c' || echo './'`zoom-region.c; \
then mv -f ".deps/magnifier-zoom-region.Tpo"
".deps/magnifier-zoom-region.Po"; else rm -f
".deps/magnifier-zoom-region.Tpo"; exit 1; fi
zoom-region.c: In function `zoom_region_source_rect_from_view_rect':
zoom-region.c:697: warning: implicit declaration of function `round'
zoom-region.c: At top level:
zoom-region.c:562: warning: `zoom_region_clip_to_scaled_pixmap' defined
but not used
/bin/sh ../libtool --tag=CC --mode=link gcc -I /usr/include
-I /usr/include -g -O2 -Wall -I /usr/include -DORBIT2=1 -pthread
-I/usr/include/at-spi-1.0 -I/usr/include/libbonobo-2.0
-I/usr/include/atk-1.0 -I/usr/include/gtk-2.0 -I/usr/include/glib-2.0
-I/usr/lib/glib-2.0/include -I/usr/include/orbit-2.0
-I/usr/include/bonobo-activation-2.0 -I/usr/lib/gtk-2.0/include
-I/usr/include/cairo -I/usr/include/pango-1.0   -I /usr/include
-I /usr/include -g -O2 -Wall   -o magnifier  magnifier-magnifier-main.o
magnifier-magnifier.o magnifier-zoom-region.o magnifier-damage-client.o
magnifier-GNOME_Magnifier-skels.o magnifier-GNOME_Magnifier-common.o
-Wl,--export-dynamic -pthread -L/usr/X11R6/lib -lloginhelper -lspi
-lbonobo-2 -lbonobo-activation -lORBit-2 -lgthread-2.0 -lgtk-x11-2.0
-lgdk-x11-2.0 -latk-1.0 -lpangocairo-1.0 -lpango-1.0 -lcairo -lfreetype
-lfontconfig -lXrender -lX11 -lXext -lpng12 -lz -lgdk_pixbuf_xlib-2.0
-lgdk_pixbuf-2.0 -lm -lgobject-2.0 -lgmodule-2.0 -ldl -lglib-2.0
libgnome-mag.la -L/usr/X11R6/lib  -lSM -lICE -lX11   -L/usr/X11R6/lib
-lXtst  -L/usr/X11R6/lib -lXdamage  -L/usr/X11R6/lib -lXfixes -lpopt
gcc -I /usr/include -I /usr/include -g -O2 -Wall -I /usr/include
-DORBIT2=1 -pthread -I/usr/include/at-spi-1.0
-I/usr/include/libbonobo-2.0 -I/usr/include/atk-1.0
-I/usr/include/gtk-2.0 -I/usr/include/glib-2.0
-I/usr/lib/glib-2.0/include -I/usr/include/orbit-2.0
-I/usr/include/bonobo-activation-2.0 -I/usr/lib/gtk-2.0/include
-I/usr/include/cairo -I/usr/include/pango-1.0 -I /usr/include
-I /usr/include -g -O2 -Wall -o .libs/magnifier
magnifier-magnifier-main.o magnifier-magnifier.o magnifier-zoom-region.o
magnifier-damage-client.o magnifier-GNOME_Magnifier-skels.o
magnifier-GNOME_Magnifier-common.o -Wl,--export-dynamic -pthread
-L/usr/X11R6/lib /usr/lib/libloginhelper.so /usr/lib/libspi.so /usr/lib/libgailutil.so -L/usr/X11/lib /usr/lib/libgnomecanvas-2.so /usr/lib/libart_lgpl_2.so /usr/lib/libbonobo-2.so /usr/lib/libbonobo-activation.so /usr/lib/libORBitCosNaming-2.so /usr/lib/libgtk-x11-2.0.so /usr/lib/libgdk-x11-2.0.so /usr/lib/libatk-1.0.so /usr/lib/libpangocairo-1.0.so /usr/lib/libpangoft2-1.0.so /usr/lib/libpango-1.0.so /usr/lib/libcairo.so /usr/lib/libfontconfig.so /usr/lib/libfreetype.so /usr/lib/libexpat.so -lXrender -lXext -lpng12 -lz /usr/lib/libgdk_pixbuf_xlib-2.0.so /usr/lib/libgdk_pixbuf-2.0.so ./.libs/libgnome-mag.so /usr/lib/libORBit-2.so -lm /usr/lib/libgmodule-2.0.so -ldl /usr/lib/libgobject-2.0.so /usr/lib/libgthread-2.0.so -lpthread /usr/lib/libglib-2.0.so -lSM -lICE -lX11 -lXtst -lXdamage -lXfixes /usr/lib/libpopt.so
creating magnifier
make[1]: Leaving directory `/home/kadu/gnome-mag/unstable/magnifier'

Any help will be very appreciated.
-- 
Carlos Eduardo Rodrigues Diógenes