[R] R-1.9.0: make error on slackware-current!

[Qian Kevin]

My box: Slackware-current, Xfree 4.4.
ERROR as follows:

gcc -I. -I../../../src/include -I../../../src/include -I/usr/X11R6/include 
-I/usr/local/include -DHAVE_CONFIG_H -D__NO_MATH_INLINES -mieee-fp -fPIC  
-g -O2 -c dataentry.c -o dataentry.lo
In file included from dataentry.c:31:
/usr/X11R6/include/X11/Xlib.h:1390: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:1478: error: parse error before "char"
/usr/X11R6/include/X11/Xlib.h:1506: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:1510: error: parse error before "char"
/usr/X11R6/include/X11/Xlib.h:1532: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:1567: error: parse error before '*' token
/usr/X11R6/include/X11/Xlib.h:1576: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:1601: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:1651: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:1657: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:1704: error: parse error before "char"
/usr/X11R6/include/X11/Xlib.h:1743: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:1984: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:2068: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:2321: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:2331: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:2403: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:2413: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:2571: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:2586: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:2779: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:2846: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:2851: error: parse error before "char"
/usr/X11R6/include/X11/Xlib.h:2965: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:2991: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3002: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3027: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3036: error: parse error before "char"
/usr/X11R6/include/X11/Xlib.h:3049: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3192: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3241: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3273: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3364: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3371: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3391: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3397: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3409: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3419: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3429: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3435: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3536: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3553: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3604: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3647: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3653: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3659: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3665: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3673: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3681: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3689: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3701: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3713: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3760: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3771: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3782: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3793: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3804: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xlib.h:3815: error: parse error before "_Xconst"
In file included from dataentry.c:32:
/usr/X11R6/include/X11/Xutil.h:566: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xutil.h:606: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xutil.h:666: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xutil.h:678: error: parse error before "_Xconst"
/usr/X11R6/include/X11/Xutil.h:801: error: parse error before "_Xconst"


Help me!