Arkadaşlar serverde 4 tane sorunsuz irc server kurdum ama bundan sonrakilerde şu hatayı alıyorum

bu eggdrop için verdiği hata
[xxx@server ~]$ cd eggdrop1.6.18
[xxx@server eggdrop1.6.18]$ ./configure
This is Eggdrop's GNU configure script.
It's going to run a bunch of tests to hopefully make your compile
work without much twiddling.
checking for gcc... gcc
checking for C compiler default output file name... configure: error: C compiler cannot create executables
See `config.log' for more details.
[xxx@server eggdrop1.6.18]$

buda unreal için verdiği hata
Would you like any more parameters to configure?
Write them here:
[]->
./configure --with-showlistmodes --enable-hub --with-listen=5 --with-dpath=/home/yyy/Unreal3.2 --with-spath=/home/yyy/Unreal3.2/src/ircd --with-nick-history=2000 --with-sendq=3000000 --with-bufferpool=18 --with-hostname=server.zzz.com --with-permissions=0600 --with-fd-setsize=1024 --enable-dynamic-linking
checking for gcc... gcc
checking for C compiler default output... configure: error: C compiler cannot create executables

yardımlarınızı bekliyorum şimdiden teşekkür ederim.
işletim sistemim linux CENTOS Enterprise 4.5 i686

denediklerim

[root@server /]# yum install gcc
Setting up Install Process
Setting up repositories
update 100% |=========================| 951 B 00:00
rpmforge 100% |=========================| 1.1 kB 00:00
base 100% |=========================| 1.1 kB 00:00
addons 100% |=========================| 951 B 00:00
http://mirrors.ee.teiath.gr/CentOS/4...ata/repomd.xml: [Errno 14] HTTP Error 404: Not Found
Trying other mirror.
http://ftp-stud.fht-esslingen.de/pub...ata/repomd.xml: [Errno 4] IOError: <urlopen error (-2, 'Name or service not known')>
Trying other mirror.
extras 100% |=========================| 1.1 kB 00:00
Reading repository metadata in from local files
Excluding Packages in global exclude list
Finished
Parsing package install arguments
Nothing to do
[root@server /]#

ve şöyle bir durumda war root shhtan mesela userin kuramadığı unreali root kurabiliyo