#45 ncrcat crashes for record dimension with non-time units

[atw]

When concatenating along a record dimension with non-time units, e.g. after using ncpdq to permute longitude into the record dimension for concatenation, ncrcat v4.0.8 crashes inside libudunits2. Removing the record dimension's units, or changing them to something like "days since 0001-01-01 00:00:00", gives no crash.

Output of `uname -a` on my platform:

Linux an003 2.6.18-238.12.1.el5 #1 SMP Tue May 31 13:22:04 EDT 2011 x86_64 x86_64 x86_64 GNU/Linux

Demo of the bug:

#!/bin/csh -f
# This script produces the following output:
#
# ncrcat 4.0.8:
# *** glibc detected *** /usr/local/nco-4.0.8/bin/ncrcat: double free or corruption (fasttop): 0x0000000015332de0 ***
# ======= Backtrace: =========
# /lib64/libc.so.6[0x2ae9857cf45f]
# /lib64/libc.so.6(cfree+0x4b)[0x2ae9857cf8bb]
# /app/udunits-2.1.19/lib/libudunits2.so.0[0x2ae985428478]
# /app/udunits-2.1.19/lib/libudunits2.so.0(ut_free+0x25)[0x2ae985429cb5]
# /usr/local/nco-4.0.8/lib/libnco-4.0.8.so(nco_cln_clc_dff+0x14b)[0x2ae9849762eb]
# /usr/local/nco-4.0.8/lib/libnco-4.0.8.so(nco_cln_clc_org+0xd5)[0x2ae984975765]
# /usr/local/nco-4.0.8/lib/libnco-4.0.8.so(nco_lmt_evl+0x426)[0x2ae984986676]
# /usr/local/nco-4.0.8/bin/ncrcat[0x405d83]
# /lib64/libc.so.6(__libc_start_main+0xf4)[0x2ae98577a994]
# /usr/local/nco-4.0.8/bin/ncrcat[0x4041b9]
# ...

ncgen -o f1.nc << EOF
netcdf f1 {
dimensions:
lon = UNLIMITED ; // (1 currently)
variables:
float temp(lon) ;
temp:missing_value = -1.e+10f ;
float lon(lon) ;
lon:units = "degrees_E" ;
data:
temp = 13.99574 ;
lon = -278.5 ;
}
EOF

ncgen -o f2.nc << EOF
netcdf f2 {
dimensions:
lon = UNLIMITED ; // (1 currently)
variables:
float temp(lon) ;
temp:missing_value = -1.e+10f ;
float lon(lon) ;
lon:units = "degrees_E" ;
data:
temp = 14.30086 ;
lon = -188.5 ;
}
EOF

ncrcat -O -h f1.nc f2.nc f.nc

[Charlie Zender]

Thank you for this report. I have reproduced the bug and am working on a solution.

[Charlie Zender]

I have not forgotten this bug. Neither have I worked enough on it. I will make it a priority when the new programmer arrives...

[Charlie Zender]

Thanks for reporting this and for your patience. Code patch is now committed and will be in next stable release.
cz