Fix check_gcc_config_and_reset_if_necessary fn

Previously tried to run gcc to get version number, which fails
when the gcc config is invalid...

buildkernel

@@ -31,7 +31,7 @@ shopt -s nullglob
 # ********************** variables ********************* 
 PROGNAME="$(basename "${0}")"
 CONFFILE="/etc/${PROGNAME}.conf"
-VERSION="1.0.12"
+VERSION="1.0.13"
 ETCPROFILE="/etc/profile"
 DEFAULTEFIBOOTFILE="bootx64.efi"
 EFIBOOTFILE="${DEFAULTEFIBOOTFILE}"
@@ -116,6 +116,7 @@ USE_PLYMOUTH=true
 VERBOSITYFLAG=""
 ASKFLAG=""
 ALERTFLAG=""
+PORTAGEINFO=""
 # following array variables set by find_all_gpg_keyfile_partitions function
 declare -a GPGUUIDS GPGPARTNAMES GPGDEVNAMES GPGPARTNUMS
 # following array variables set by find_all_luks_partitions function
@@ -249,14 +250,33 @@ check_file_exists() {
         die "File '${1}' does not exist"
     fi
 }
+read_portage_info_if_necessary() {
+    if [ -z "${PORTAGEINFO}" ]; then
+        show "Checking Portage configuration, please wait..."
+        PORTAGEINFO="$(emerge --info)"
+    fi
+}
 check_gcc_config_and_reset_if_necessary() {
     # check if gcc-config exists with an error - if it does, then
     # attempt to set one based on the current gcc version number
     if ! gcc-config --get-current-profile >/dev/null 2>&1; then
         # unset or invalid, attempt to force this to the current gcc
         # version
-        local GCC_VERSION="$(gcc --version | head -n 1 | sed 's/^.* //')"
-        if gcc-config "${GCC_VERSION}"; then
+        read_portage_info_if_necessary
+        local CHOST="$(grep '^CHOST=.*' <<<"${PORTAGEINFO}")"
+        CHOST="$(cut -d\" -f2 <<< ${CHOST})"
+        local GCC_VERSION=""
+        # can't be sure we have eix installed
+        if eix --version >/dev/null 2>&1; then
+            # we do, so can cleanly check latest installed gcc version
+            GCC_VERSION="$(eix --installed --exact sys-devel/gcc --format '<installedversions:NAMEVERSION>' --versionsort | tail -n 1)"
+            GCC_VERSION="${GCC_VERSION##*gcc-}"
+        else
+            # we don't, have to hack the most recent gcc version
+            GCC_VERSION="$(ls -1v "/usr/${CHOST}/gcc-bin" | tail -n 1)"
+        fi
+        local FULL_GCC_ID="${CHOST}-${GCC_VERSION}"
+        if gcc-config "${FULL_GCC_ID}"; then
             warning "gcc configuration was reset"
             if [ -s "${ETCPROFILE}" ]; then
                 set +e

buildkernel.8

@@ -1,4 +1,4 @@
-.TH BUILDKERNEL 8 "Version 1.0.12: August 2015"
+.TH BUILDKERNEL 8 "Version 1.0.13: November 2015"
 .SH NAME
 buildkernel \- build secure boot kernel, save to EFI system partition
 .SH SYNOPSIS

buildkernel.conf.5

@@ -1,4 +1,4 @@
-.TH BUILDKERNEL 5 "Version 1.0.12: August 2015"
+.TH BUILDKERNEL 5 "Version 1.0.13: November 2015"
 .SH NAME
 buildkernel.conf \- a configuration file for \fBbuildkernel\fR(8)
 .SH SYNOPSIS