configure: error: no acceptable C compiler found in $PATH

wget http://dl.fedoraproject.org/pub/epel/7/x86_64/s/strongswan-5.4.0-2.el7.x86_64.rpm
rpm -ivh strongswan-5.4.0-2.el7.x86_64.rpm
yum install -y gmp-devel
yum install libxml2-devel openssl-devel
wget http://download.strongswan.org/strongswan.tar.gz
tar -xzvf strongswan.tar.gz
cd strongswan
cd strongswan-5.5.1/
./configure –sysconfdir=/etc –enable-openssl –enable-nat-transport –disable-mysql –disable-ldap –disable-static –enable-shared –enable-md4 –enable-eap-mschapv2 –enable-eap-aka –enable-eap-aka-3gpp2 –enable-eap-gtc –enable-eap-identity –enable-eap-md5 –enable-eap-peap –enable-eap-radius –enable-eap-sim –enable-eap-sim-file –enable-eap-simaka-pseudonym –enable-eap-simaka-reauth –enable-eap-simaka-sql –enable-eap-tls –enable-eap-tnc –enable-eap-ttls
configure: WARNING: unrecognized options: –enable-nat-transport
checking for a BSD-compatible install… /usr/bin/install -c
checking whether build environment is sane… yes
checking for a thread-safe mkdir -p… /usr/bin/mkdir -p
checking for gawk… gawk
checking whether make sets $(MAKE)… yes
checking whether make supports nested variables… yes
checking whether UID ‘0’ is supported by ustar format… yes
checking whether GID ‘0’ is supported by ustar format… yes
checking how to create a ustar tar archive… gnutar
checking whether make supports nested variables… (cached) yes
checking for pkg-config… /usr/bin/pkg-config
checking pkg-config is at least version 0.9.0… yes
checking for a sed that does not truncate output… /usr/bin/sed
checking configured UDP ports (500, 4500)… ok
checking for gcc… no
checking for cc… no
checking for cl.exe… no
configure: error: in `/data/soft/strongswan-5.5.1′:
configure: error: no acceptable C compiler found in $PATH
See `config.log’ for more details


You need to install a compiler to compile. The solutions in the mentioned question should work:

yum install gcc
or

yum groupinstall “Development tools”
After that, try to run your compiler to make sure everything is aligned:

gcc