Bugs Fixed in Version 3.8

• absolute_file_name/2: could crash under IRIX; nested compound terms allowed
• call_cleanup/2: efficiency
• close/1: efficiency; handling the standard streams
• format/[2,3]: ~N didn't work as expected; are now meta-predicates--needed by the ~@ format spec
• load_files/[1,2]: avoid changing directory; don't loop on duplicate exports
• load_foreign_resource/1: filenames containing periods on Windows NT
• print_message/2: in runtime systems
• prolog_load_context/2: value of term_position
• reinitialise/0: sequencing of events
• save_program/[1,2]: fastcode handling; file mode creation masks; in runtime systems
• write_term/[1,2]: the indented(true) option and non-ground terms
• library(db): efficiency of term deletion
• library(heaps): delete_from_heap/4
• library(objects): the new/2 method; cyclic dependencies
• library(random): determinacy and efficiency
• library(sockets): noisy startup on Windows; block buffering is now the default; socket_buffering/4 added
• library(system): sleep/1 admits floats as well as integers
• library(terms): subsumes_chk/2 and variant/2 now don't unblock goals
• glue code generator: incorrect translation of +chars; syntax error messages were suppressed
• all system messages go via the print_message/2 interface
• input argument checking is generally stricter
• resources are unloaded in LIFO order but loaded in FIFO order at save/restore
• CLP(Q,R): answer constraint projection
• problems with bignums and big terms in .ql files
• detecting invalid goals in meta-calls, asserts, load_files/[1,2]
• spurious redefinition warnings
• bignum quotient/remainder on 64-bit architectures
• compiler: complexity of compiling multiple clauses with same key, code generation quality for inline goals
• memory manager: avoiding dangling pointers on Windows, better reclamation of dead clauses and predicates, using dynamic hashing and hashpjw for atoms, keeping predicate tables as small as possible, avoiding stack overflow if multiple goals get simultaneously unblocked, better reuse of free memory blocks
• garbage collector: removing redundant trail entries for mutables, improved scope and speed of generational garbage collection
• callbacks to Prolog while reading from the terminal
• printing atoms with character codes in 27...31
• reading atoms with \c
• Floating point NaN (Not a Number). Now behaves consistently across platforms. In particular, fixed Windows related bugs with arithmetic on and printing of NaN.
  • Arithmetic comparisons involving NaN now fails (except =\=). Note that X is nan, X =:= X fails.
  • Term order for NaN is now defined and the same for all platforms. There is a single NaN and it lies between (the float) +inf and the integers.