Merged
requested to merge patrick.jaap_at_tu-dresden.de/dune-elasticity:fix/adolc-trace_off into master
Following the doc at
https://github.com/coin-or/ADOL-C/blob/master/ADOL-C/doc/adolc-manual.pdf
this enforces writing the tapes to disk and has nothing to do with the actual taping. From the doc:
"By setting the optional integer argument file of trace_off to 1, the user may force a
numbered tape file to be written even if the tape array (buffer) does not overflow. If the
argument file is omitted, it defaults to 0, so that the tape array is written onto a tape file
only if the length of any of the buffers exceeds [OLVT]BUFSIZE elements."