news for release 960 since 959
------------------------------

* fixed various issues pointed out by Stefan Hengelein:
  - fixed incremental usage of 'picosat_adjust'
  - added CPP fixes (STATS, NO_BINARY_CLAUSE versus TRACE mix-ups)
  - removed redundant explicit set to zero on reset
* fixed various usage bugs with 'picomus' (thanks to Stefan Hengelein)
* removed '-fno-strict-aliasing' (thanks to Jerry James)

news for release 959 since 953
------------------------------

* fixed header comments

* fixed minor compilation issues

* fixed unitialized memory access problem for 'picosat_deref_partial'
  and another issue with partial models

* added 'picosat_add_arg' and 'picosat_add_lits'

* '--plain' and 'picosat_set_plain' to disable failed literal probing

* new '#define PICOSAT_REENTRANT_API' in 'picosat.h'

* added manager so no more global variables
  (allows multiple instances, requires manager object)

news for release 951 since 941
------------------------------

* cleaned up code (based on comments by Donald Knuth)

* lreduce=O(conflicts^.5)

* added 'picosat_visits' and 'picosat_decisions'

* added '--partial' command line option

* added 'picosat_deref_partial' and 'picosat_save_original_clauses'

* added 'picomcs' as example for MSS computation

news for release 941 since 936
------------------------------

* added 'picogcnf'

* added All-SAT mode ('--all' command line option)

* statistics include time spent in failed literal preprocessing (probing)

* 'picosat_failed_context' for 'push & pop'
   (and tested failed assumptions for 'push & pop')

* 'picosat_simplify' for forced garbage collection

* undefined NFL, defined NADC (= failed literals on, ADC's off)

* 'picosat_push' and 'picosat_pop' (beta version)

* fixed some issues related to binary clause handling and 
  generating list of failed assumptions

news for release 936 since 935
------------------------------

* simple minimal unsatisfiable core (MUS) extractor 'picomus'
  (example for using 'picosat_mus_assumptions' and 'picosat_coreclause')

* added 'picosat_mus_assumptions'

* added 'picosat_{set_}propagations'

* new 'int' return value for 'picosat_enable_trace_generation' to
  check for trace code being compiled

news for release 935 since 926
------------------------------

* added 'picosat_failed_assumptions' (plural)

* new '-A <failedlits>' command line option

* fixed failed assumption issues

* added 'picosat_remove_learned'

* added 'picosat_reset_{phases,scores}'

* added 'picosat_set_less_important_lit'

* added 'picosat_res'

news for release 926 since 846
------------------------------

* random initial phase (API of 'picosat_set_default_phase' changed)

* fixed accumulative failed assumption (multiple times)

* fixed missing original clause in core generation with assumptions

* fixed debugging code for memory allocation

* shared library in addition to static library

* removed potential UNKNOWN result without decision limit

* added picosat_set_more_important_lit

* added picosat_coreclause

* propagation of binary clauses until completion

* fixed API usage 'assume;sat;sat'

* literals move to front (LMTF) during traversal of visited clauses

* switched from inner/outer to Luby style restart scheduling

* less agressive reduce schedule

* replaced watched literals with head and tail pointers

* add 'picosat_failed_assumption', which allows to avoid tracing and core
  generation, if one is only interested in assumptions in the core

* fixed a BUG in the generic iterator code of clauses
  (should rarely happen unless you use a very sophisticated malloc lib)

news for release 846 since 632
------------------------------

* cleaned up assumption handling (actually removed buggy optimization)

* incremental core generation 

* experimental 'all different constraint' handling as in our FMCAD'08 paper

* new API calls: 

  - picosat_add_ado_lit       (add all different object literal)
  - picosat_deref_top_level   (deref top level assignment)
  - picosat_changed           (check whether extension was possible)
  - picosat_measure_all_calls (per default do not measure adding time)
  - picosat_set_prefix        (set prefix for messages)

* 64 bit port (and compilation options)

* optional NVSIDS visualization code

* resource controlled failed literal implementation

* disconnect long clauses satisfied at lower decision level

* controlling restarts
