Here is a compilation of arangodb errors - configure

Question

What's the problem with the configure code?
ERROR INFO：
./configure: line 9746: syntax error near unexpected token `else'
./configure: line 9746: `else'
CONFIGURE CODE：
_ACEOF
rm -f conftest.$ac_objext
if { (ac_try="$ac_compile"
case "(($ac_try" in
*\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
*) ac_try_echo=$ac_try;;
esac
eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\""
$as_echo "$ac_try_echo") >&5
(eval "$ac_compile") 2>conftest.er1
ac_status=$?
grep -v '^ *+' conftest.er1 >conftest.err
rm -f conftest.er1
cat conftest.err >&5
$as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
(exit $ac_status); } && {
test -z "$ac_c_werror_flag" ||
test ! -s conftest.err
} && test -s conftest.$ac_objext; then
else
$as_echo "$as_me: failed program was:" >&5
sed 's/^/| /' conftest.$ac_ext >&5
OPENSSL_WARNING=" WARNING: OpenSSL version should be 1.0.1g or higher"
{ $as_echo "$as_me:$LINENO: WARNING: OpenSSL version should be 1.0.1g or higher." >&5
$as_echo "$as_me: WARNING: OpenSSL version should be 1.0.1g or higher." >&2;}
fi

Answer 1

There's something wrong with your configure script it seems. In the version on Github I see this code:
if ac_fn_c_try_compile "$LINENO"; then :
else
OPENSSL_WARNING=" WARNING: OpenSSL version should be 1.0.1g or higher"
{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: OpenSSL version should be 1.0.1g or higher." >&5
$as_echo "$as_me: WARNING: OpenSSL version should be 1.0.1g or higher." >&2;}
fi
The breaking difference with yours is that yours lacks the colon after then.
For a more detailed explanation about the colon operator in bash, see What is the purpose of the : (colon) GNU Bash builtin? . The short version, here it acts like some kind of "no-op".