new parser does not handle ctrl-C

[Michael D. Godfrey]

John,

I suspect that you are still working on the parser, but you
might want to know that the current version no longer handles
ctrl-C as it did before:  The following shows the new behavior,
which leaves the system in a non working state after ctrl-C.
First, Octave 3.6.3 to show how it worked before, then current
devel. (The command with unbalanced ( starts the trouble.)

[pbdsl3:nons_test_data] /usr/bin/octave
GNU Octave, version 3.6.3
Copyright (C) 2012 John W. Eaton and others.
This is free software; see the source code for copying conditions.
There is ABSOLUTELY NO WARRANTY; not even for MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  For details, type `warranty'.

Octave was configured for "x86_64-redhat-linux-gnu".

Additional information about Octave is available at http://www.octave.org.

Please contribute if you find this software useful.
For more information, visit http://www.octave.org/help-wanted.html

Read http://www.octave.org/bugs.html to learn how to submit bug reports.

For information about changes from previous versions, type `news'.

octave:1> anls = 1./((2*NL) + 1);
error: `NL' undefined near line 1 column 15
octave:1> anls = 1./((2*3) + 1);
octave:2> anls = 1./((2*3) + 1)
anls =  0.14286
octave:3> sum([1 2 3 4]*anls
>
> ^C
octave:3> anls = 1./((2*3) + 1)
anls =  0.14286
octave:4> quit
===========================here I try the devel Octave:
[pbdsl3:nons_test_data] oct
octave:1> anls = 1./((2*3) + 1)
anls =  0.14286
octave:2> sum([1 2 3 4]*anls
> ^C
octave:2> anls = 1./((2*3) + 1)
> )
parse error:

  syntax error

>>> )
    ^

octave:2> anls = 1./((2*3)) + 1)
parse error:

  syntax error

>>> anls = 1./((2*3)) + 1)
                          ^

octave:2> )
*** glibc detected *** octave: free(): invalid pointer: 
0x0000000001eef448 ***
======= Backtrace: =========
/lib64/libc.so.6[0x314f27ca8e]
/usr/local/lib/octave/3.7.2+/liboctinterp.so.1(_Z10octave_lexP7YYSTYPEPv+0x17a1)[0x7fe7def928c1]
/usr/local/lib/octave/3.7.2+/liboctinterp.so.1(_Z17octave_pull_parseP13octave_pstateP13octave_parser+0x31)[0x7fe7defa2021]
/usr/local/lib/octave/3.7.2+/liboctinterp.so.1(_Z9main_loopv+0x10b)[0x7fe7df29be8b]
/usr/local/lib/octave/3.7.2+/liboctinterp.so.1(octave_execute_interpreter+0x84d)[0x7fe7deb5c32d]