Compare Ant version used `expr` command , maybe is a wrong way.

[gimlyu]

execute ./configure output

Building Java Library ........ : no

javac,java ,ant command available, and the ant version is 1.10.1 (bottled)
use vim open configure file and find the code at 18844 line is :

ANT_VALID=expr $($ANT -version 2>/dev/null | sed -n 's/.*version \([0-9\.]*\).*/\1/p') \>= 1.7

Maybe use expr command comparing version is inadvisable.

test :

➜ a=expr 1.10.1 \>= 1.8
➜ echo $a
0
➜ a=expr 1.10.1 \>= 1.0
➜ echo $a
1

It is a bug ?