AWLF catenate() unit test gives wrong answers

Bugzilla Link	1082
Created on	May 15, 2013 14:35
Resolution	FIXED
Resolved on	May 15, 2013 19:40
Version	svn
OS	Linux
Architecture	PC
Attachments	bug1082.sac

Extended Description

sac2c -V
sac2c v1.00-beta (Haggis And Apple)
 developer rev 18145 linux-gnu_x86_64
 (Wed May 15 09:23:39 EDT 2013 by sac)
The attached unit test, if compiled this way:
sac2c bugtuesday.sac -doawlf -nowlf  -DBROKEN 
produces incorrect answers.
The culprit appears to be CF, in particular,
SCCFprf_idx_modarray_AxSxS and its friends in the
indexed-assign business.
We start with an N_array of N_num (or equivalent):
  
  arr = [ 1, 2];
and are doing:
  arr[1] = flatid;
The code then replaces one element of arr by an N_id, producing a
mongrel that is partially flattened:
  arr = [ 1, flatid];
This appears to bring on the fault. So, the actual 
problem, I think, lies elsewhere, in code that is unable
to tolerate mongrels.