[GRASS5] Some strange tcl.h not found error (Redhat 8)

[Markus Neteler]

Today I tried to configure 5.7 on a Redhat-8 box. To my surprise
tcl.h is not found although present. Does anyone have an idea?

uname -a
Linux localhost 2.4.18-14 #1 Wed Sep 4 13:35:50 EDT 2002 i686 i686 i386 GNU/Linux

configure <params>
[...]
checking for gdImagePng in -lgd... yes
checking for gdImageGif in -lgd... no
checking for gdImageCreateTrueColor in -lgd... no
checking whether to use Tcl/Tk... yes
checking for location of Tcl/Tk includes... /usr/include
checking for tcl.h... no
configure: error: *** Unable to locate Tcl includes.

tail config.log
configure:9508: checking whether to use Tcl/Tk
configure:9528: checking for location of Tcl/Tk includes
configure:9554: checking for tcl.h
configure:9562: gcc -E  -I/usr/include  conftest.c >/dev/null 2>conftest.out
configure: failed program was:
#line 9557 "configure"
#include "confdefs.h"
#include <tcl.h>


ls -la /usr/include/tcl.h
-rw-r--r--    1 root     root        57868 ago 20  2002 /usr/include/tcl.h

Thanks,

 Markus