FULL PRODUCT VERSION :
java version "1.7.0_21"
OpenJDK Runtime Environment (IcedTea 2.3.9) (7u21-2.3.9-5)
OpenJDK 64-Bit Server VM (build 23.7-b01, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Linux 3.12-1-amd64 #1 SMP Debian 3.12.9-1 (2014-02-01) x86_64 GNU/Linux

A DESCRIPTION OF THE PROBLEM :
Formatter throws an java.lang.ArrayIndexOutOfBoundsException when the format string is "%.1g" and the value is 0.
It is ok with a non-null value.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Execute the attached code


ERROR MESSAGES/STACK TRACES THAT OCCUR :
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException
at java.lang.System.arraycopy(Native Method)
at java.util.Formatter$FormatSpecifier.addZeros(Formatter.java:3401)
at java.util.Formatter$FormatSpecifier.print(Formatter.java:3295)
at java.util.Formatter$FormatSpecifier.print(Formatter.java:3190)
at java.util.Formatter$FormatSpecifier.printFloat(Formatter.java:2757)
at java.util.Formatter$FormatSpecifier.print(Formatter.java:2708)
at java.util.Formatter.format(Formatter.java:2488)
at java.util.Formatter.format(Formatter.java:2423)
at test.main(test.java:7)

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.util.Formatter;

public class test {

    public static void main(String[] args) {
Formatter fmt = new Formatter();
fmt.format("%.1g", 0.);

System.out.println(fmt.toString());
    }
}
---------- END SOURCE ----------