added sample 'configure' file; boiler now generates softinclude for Jamrules.configure

[k8jam.git] / doc / RELNOTES

===============================================================================
===============================================================================


Release notes for Jam 2.5
(aka Jam - make(1) redux)

1.  Release info:

  Jam 2.5
  August 19, 2004
  VERSION 2.5

  (n.b. Jam 2.5 is merely Jam 2.5rc3 of April 2003 with the rc3
  moniker removed.)

2.  Compatibility

  Jam 2.5 is upward compatible with Jam 2.4

  The Jam 2.5 language is a superset of the 2.4 language;
  Jamfiles, Jambase, and other rulesets used in 2.4 can be used
  with the 2.5 language support.

3.  Changes since 2.4.

3.1.  Changes to Jam Language

  The 'return' statement now actually returns, and there are now
  break & continue statements for for & while loops.

3.2.  Jambase Changes

  MkDir now grists directories with 'dir', so that directory
  targets can be distinguished from other targets.

  SubDir now allows multiple overlapping roots (top level
  directories): the first SubDir of a new root uses the CWD of
  jam to set that root; subsquent SubDirs use the current SUBDIR
  to set the new root.  New FSubDirPath to compute a path (given
  SubDir arguments) and SubRules to include another root's
  Jamrules.  Jamrules only included if present; no error issued
  if no Jamrules file.

  Using SubDir to include a subpart of an SubDir tree now works.
  Previously, you could only include the root of another SubDir
  tree.  This example includes the ../server/support/Jamfile,
  without getting confused as to the current directory:

    SubDir ALL src builds ;
    SubInclude ALL src server support ;

  $(RMDIR) has been defined for NT and defaulted to $(RM)
  everwhere else.  Not much tested.  For Michael Champigny.

  GenFile actions (on UNIX) now put . in the PATH for the execution
  of the command, so that (at least) when jam builds itself . does
  not need to be in the global path.  It is the rare case where a
  target bound in the current directory can't be used directly,
  so we fudge it by setting PATH.

  Undocumented support for SUBDIRRULES, user-provided rules
  to invoke at the end of the SubDir rule, and SUBDIRRESET,
  SUBDIR variables to reset (like SUBDIRC++FLAGS, SUBDIRHDRS, etc)
  for each new SubDir.

3.3   'jam' Changes (See Jam.html)

  The whole /MR of Jam's name has been dropped.  It was intended
  to avoid trademark infringement of JYACC's JAM, but as far as
  we can tell (a) it wasn't enough to avoid infringement and (b)
  the trademark has lapsed anyhow.

  If header dependencies cause an object to be recompiled and
  the source file is a temporary, the temporary is now
  reconstructed.  Previously, headers weren't considered when
  deciding when to reconstruct a temporary.

  -d has been reworked to make it easier to display more useful
  tracing information separate from the debugging gunk:

    -da - show all actions (formerly -d2)
    -dc - show 'causes' for rebuilding (new output)
    -dd - show dependencies (new output)
    -dm - show make graph (aka -d3)
    -dx - show executable text (formerly -d2)

  -dd is new, and more display options are anticipated.

  -n now implies -dax.

  The message "...using xxx..." now only shows up with -da.

  Jam.html was extensively updated, in an attempt at lucidity.

3.4.  Jam internal code changes

  Removed spurious search() in 'on' statement handling, thanks
  (again) to Ingo Weinhold.

  Fix 'includes' support so that included files aren't treated
  as direct dependencies during the command execution phase.  If
  an included file failed to build, make1() would bypass the
  including file.  Now make0() appends each child's 'includes'
  onto its own 'depends' list, eliminating 'includes'-specific
  code in make0() and make1().

  Rewrite of the past: updated all jam's source with comments to
  reflect changes since about 2.3, very early 2001.


4.  Fixed bugs

  Fixed the description of the :E modifier in Jam.html.

  Setting target-specific variables while under the influence of
  the target's target-specific variables caused the _global_ values
  to be modified.  This happened both during header file scanning
  (HdrRule is called when target-specific variables are in effect)
  and with the "on target statement" syntax.  Now setting
  target-specific variables works again.  Thanks to Matt Armstrong.

  Setting "var on target ?= value" now works as expected: if the
  variable is already set on the target, it is left unchanged.
  Previously, ?= was ignored and the variable was set anyway.
  Thanks to Chris Antos.

  Variable expansion in actions has always put an extra blank
  space after the last list element, but the expansion is described
  in the code as "space separated".  Now the last blank is suppressed
  to match.  From Miklos Fazekas.

  The temp file name used by jam for .bat files on NT now contains
  jam's pid, so that multiple jams can run on the same system (with
  the same $TEMP).  Thanks to Steve Anichini.

  Several uninitialized memory accesses have been corrected in
  var_expand() and file_archscan(), thanks to Matt Armstrong.

5.  Porting

  The Makefile now uses $(EXENAME) (./jam0 on UNIX, .\jam0.exe
  on NT) instead of just "jam0", so that . doesn't need to be in
  your PATH to bootstrap.

  MACOSX updates: use 'ar' instead of libtool, as libtool can't
  update a library and we archive too many things to do it in
  one go; add piles of code to file_archscan() to handle new
  BSD4.4 style "#1/nnnn" archive entry names, where the real
  entry name follows the header and nnnn is the length of the
  name.

  The jam code underwent a const-ing, to work with compilers
  that don't like "" being passed as a non-const char *.

  Compiling on solaris w/ sparc now sets OSPLAT to "sparc".
  Previously, it suppressed this, assuming (wrongly) that sparc
  was the only solaris platform.  Thanks to Michael Champigny
  <michael.champigny@intel.com>.

  Jambase no longer announces the compiler it is using on
  Windows.  It doesn't announce anything else, so why?

  Jambase no longer refers to advapi32.lib on NT, as it isn't
  needed for linking jam itself and it seems to move from
  release to release (of MS Visual Studio).

  Makefile/Jambase: BEOS updates from "Ingo Weinhold"
  <bonefish@cs.tu-berlin.de>.

  The NoCare rule can be used to suppress error messages when
  an 'include' file can't be found.

  AIX "big" archives are now supported, thanks to suggestions
  from Randy Roesler.

  MSVCDIR now works as well as MSVCNT for the Microsoft Visual C
  compiler directory.  It changed names in VC 6.0.  Thanks to
  Matt Armstrong.

  Allow jam to build with BorlandC 5.5

  For WinXP IA64; set MSVCNT to the root of the SDK and MSVCVer
  to Win64; change handle type to long long (too much to include
  windows.h?); bury IA64 in the library path in Jambase.

  Mac classic MPW Codewarrior 7 upgrades: minor compiling
  issues, new paths in Jambase for libraries and includes, and
  separate out GenFile1 that sets PATH for UNIX only, as it
  does't work under MPW (or anything other than with sh).

  Minor Cray porting: make hashitem()'s key value unsigned so
  we're guaranteed no integer overflows.

  Remove NT FQuote rule, as, \" is required to pass quotes on
  the command line.

  Remove temp .bat files created on NT.  They used to all have
  the same name and get reused, but with 2.5 the names were salted
  with the PID and they would litter $TEMP.  Now they get removed
  after being used.

===============================================================================
===============================================================================


Release notes for Jam 2.4
(aka Jam - make(1) redux)

1.  Release info:

  Jam 2.4
  March, 21, 2002
  VERSION 2.4

2.  Compatibility

  Jam 2.4 is upward compatible with Jam 2.3

  The Jam 2.4 language is a superset of the 2.3 language;
  Jamfiles, Jambase, and other rulesets used in 2.3 can be used
  with the 2.4 language support.

3.  Changes since 2.3.

3.1.  Changes to Jam Language

  The mechanism for calling rules that return values - "[ rule
  args ...]", (and 'return' in the rule body), is now a
  documented part of the language.

  Add "on <target> <rulename> <field1> ..." syntax, to invoke a
  rule under the influence of a target's specific variables.

        Add "[ on targ rule ... ]" to call a rule returning a value,
        under the influence of a target's specific variables.

  New 'Glob' builtin that returns a list of files, given a list
  of directories, and a list of filename patterns.

  New 'while expr { block }' construct.

  New :E=value modifier provides default value if variable unset.

  New :J=joinval modifier concatenates list elements into single
    element, separated by joinval.

  \ can now be used to escape a space (or any single whitespace
  character), so that you don't have to resort to quotes.

  New 'Match regexp : string' rule matches regexp against string
  and returns list of results.

  Rules can now be invoked indirectly, through variable names.
  If the variable expands to an empty list, no rule is run.
  If the variable expands to multiple entries, each rule is
  run with the same arguments.  The result of the rule invocation
  is the concatenation of the results of the rules invoked.

  'Echo' and 'Exit' now have aliases 'echo' and 'exit', since it
  is really hard to tell that these are built-in rules and not
  part of the language, like 'include'.  Real rules continue to
  start with a capital.

3.2.  Jambase Changes

  Support for YACCGEN, the suffix used on generated yacc output.

        Fix ups to have jam and p4 build with borland C 5.5,
        and minor win98 jam support for jam clean

  SubDirHdrs now takes directory names in the same format as
  SubInclude : one directory element per word.

  More portable support for specifying includes and #defines:
  New ASHDRS, CCHDRS, CCDEFS, DEFINES, ObjectDefines, FQuote,
  FIncludes, FDefines.  Ordering of cc and c++ flags grossly
  rearranged.

  Jambase has been compacted by applying the new E: and J:
  expansion modifiers.

  New SoftLink rule, courtesy of David Lindes.  It currently
  assumes you can pass a -s flag to $(LN).

3.3   'jam' Changes (See Jam.html)

  Added '-q' (quit quick) option; jam will exit promptly (as if it
  received an interrupt), as soon as any target fails.

  Added experimental '-g' (build newest sources first) option:
  all things being equal, normally targets are simply built in
  the order they appear in the Jamfiles.  With this flag, targets
  with the newest sources are built first.   From an idea by Arnt
  Gulbrandsen.  Undocumented (outside this note).

3.4.  Jam internal code changes

  jamgram.yy now defines YYMAXDEPTH to 10000, what it is on
  FreeBSD, for older yaccs that left it at 150 or so.  This is
  needed for the right-recursion now used in the grammar.

  Optimize rule compilation, with right-recursion instead of left.

        Split jam's built-in rules out to builtins.c from compile.c,
        so that compile.c only deals with the language.

        Split jam's pathsys.h from filesys.h, since they are really
        two different pieces.

  evaluate_if(), which evaluated the condition tree for 'if' and
  returned an int, has been replaced with compile_eval(), which does
  essentially the same but returns a LIST.

4.  Fixed bugs

  Missing TEMPORARY targets with multiple parents no longer spoil one
  parent's time with another.  The parents' time is used for comparison
  with dependents, but no longer taken on as the target's own time.

  'actions updated', not 'actions together', now protects targets
  from being deleted on failed/interrupted updates.

  Fixed broken $(v[1-]), which always returned an empty expansion.
  Thanks to Ian Godin <ian@sgrail.com>.

  Defining a rule within another rule, and invoking the enclosing
  rule more than once, would result in giving the first rule a
  null definition.  Fixed.

  $(d:P) now works properly on the mac, climbing up directories.
  Thanks to Miklos Fazekas <boga@mac.com>.

        No longer (sometimes) treat \ as a directory separator on
        UNIX.  It isn't supposed to be, but was due to bungled ifdefs.

        Applying just :U or :D (or :E, :J) mods no longer causes the
        variable value to be treated as a filename (parsed and rebuilt
        using the OS specific pathsys routines). Previously, if _any_
        mods were present then the value was parsed and rebuilt as if
        a filename, and that could in certain cases munge the value.
        Only the file modifiers (:GDBSM) treat the value as a
        filename.

  Four rules makeCommon, makeGrist, makeString, makeSubDir from
  jam 2.2 missing in 2.3 have been re-added, with apologies to
  dtb@cisco.com.

  Return status more likely to be correct when using -d0, now that
  targets are could as being built even with no debugging output.
  Thanks to Miklos Fazekas <boga@mac.com>.

  yyacc now suffixes all terminals it defines with _t, so that they
  don't conflict with other symbols (like RULE with the typedef
  in rules.h).  Thanks to Michael Allard.

  InstallInto now handles multiple sources properly, rather than
  acting as if each installed target depended on all sources to
  be installed.  $(INSTALLGRIST) is now the default grist for
  installed targets, rather than the hardcoded 'installed'.  Thanks
  to Stephen Goodson.

5.  Porting

  [MACINTOSH] Paths are now downshifted (internally) so as to
  handle its case insensitivity.  Thanks to Miklos Fazekas
  <boga@mac.com>.

        [NT] MS changed the macro for the IA64 Windows NT 64bit
        compiler.

  [CYGWIN] Cygwin jam porting: dance around bison and yyacc.
  Use bison's -y flag to use yacc's output file naming
  conventions, and don't use yyacc on systems whose SUFEXE is
  set.

  [VMS] The Jambase itself was not formatting the CCHDRS and
        CCDEFS properly: on VMS they can't be appended to, because
        multiple /define or /include directives don't work.  Instead
        now CCHDRS and CCDEFS is reformatted from HDRS and DEFINES
        anytime those latter two change.  This requires the recent
        change to jam to allow access to target-specific variables
        when setting other variables.

        [VMS] Remove exception call when file_dirscan() can't, for
        some reason, scan a directory.  Use a better set of #ifdefs to
        determine if we're on a vax, rather than relying on the C
        compiler being a specific version: we're able to build with
        the C++ compiler now.

  [VMS] Port new jam to run with just cxx compiler.
        (The C compiler being a extra-cost item).

        [NT] Add entry for DevStudio when the settings are already in the
        system environment.

        [NT] default $(MV) to "move /y" in Jambase.

  [MINGW] Mingw port by Max Blagai.

===============================================================================
===============================================================================


Release notes for Jam 2.3
(aka Jam - make(1) redux)

0.  Bugs fixed since 2.3.1

  PATCHLEVEL 2 - 3/12/2001

  NOCARE changed back: it once again does not applies to targets
  with sources and/or actions.  In 2.3 it was changed to apply to
  such targets, but that broke header file builds: files that are
  #included get marked with NOCARE, but if they have source or
  actions, they still should get built.

1.  Release info:

  Jam 2.3
  November 16, 2000
  VERSION 2.3
  PATCHLEVEL 1

2.  Compatibility

  Jam 2.3 is upward compatible with Jam 2.2.

  The Jam 2.3 language is a superset of the 2.2 language;
  Jamfiles, Jambase, and other rulesets used in 2.2 can be used
  with the 2.3 language support.

3.  Changes since 2.2

3.1.  Changes to Jam Language

  Rules now can have values, which can expanded into a list with
  the new "[ rule args ... ]" syntax.  A rule's value is the value
  of its last statement, though only the following statements have
  values: if (value of the leg chosen), switch (ditto), set (value
  of the resulting variable), return (its arguments).  Note that
  'return' doesn't actually return.  This support is EXPERIEMENTAL
  and otherwise undocumented.  (2.3.1)

  Because of the new way lists are processed, if a rule has no
  targets a warning message is no longer issued.

  NOCARE now applies to targets with sources and/or actions,
  rather than just those without.

3.2.  Jambase Changes

  The HDRPATTERN variable now allows for leading blanks before
  the #include, to keep up with ANSI.  By john@nanaon-sha.co.jp
  (John Belmonte) (2.2.3).

  HDRPATTERN has been adjusted to avoid mistaking cases like:

    # include <time.h> /* could be <sys/time.h> */

  MkDir now NOUPDATE's $(DOT), so that there are no dependencies
  on the current directory's timestamp.  By john@nanaon-sha.co.jp
  (John Belmonte).

  The old mock functions like makeDirName, which assigned their
  results to the variable named as their first argument, have
  been replaced with real functions using the new [] syntax.
  E.g. "makeDirName foo : bar ola" is now "foo = [ fDirName bar ]"

  Install now always does a cp/chmod/etc, rather than using
  the system's install(1), which invariably seems broken.

3.3.  Jam internal code changes

  $JAMUNAME is set on UNIX.  (2.2.4).

  Jam ANSI-fied (2.3.0).

  jam.h now defines a bunch of symbols used by the other source
  files, so as minimize compiler- and platform-specific ifdefs.

  OSVER is no longer set by jam.h (it was only set for AIX).
  Jam does not depend on this variable at all, except to set
  $(OSFULL), which is used to determine jam's build directory.
  If the user needs to distinguish between various revs of
  OSs, he must set OSVER in the environment.

4.  Fixed bugs

  Redefining a rule while it was executing could cause jam to
  crash.  Reference counts are now used to prevent that, thanks
  to Matt Armstrong.

  Logic for computing chunk size when executing PIECEMEAL rules
  has been reworked to be a little more accurate, without danger
  of overflow, at the cost of being a little more compute intensive.
  Instead of computing an estimate chunksize in the (now gone)
  make1chunk(), make1cmds() now just goes full bore and tries to
  use all args.  When that fails, it backs off by 10% of the source
  args until the command fits.  It takes a little bit more compute
  time compared to the old logic, but when you're executing actions
  to build all of Shinola it's still pretty small in the scheme
  of things.

  The NT handle leak in execunix.c has been fixed, thanks to
  Gurusamy Sarathy.  (2.2.1).

5.  Porting

  Platforms newly supported or updated:

      AmigaOS (with gcc), courtesy of Alain Penders (2.2.2).

      Beos

      CYGWIN 1.1.4, courtesy of John Belmonte <john@nanaon-sha.co.jp>.

      IBM AS400 via Visual Age on NT (primitive)

      IBM OS/390 Unix System Services

      Linux SuSE on OS390

      Linux Mips, ARM

      Lynx

      HPUX 11, IA64

      Mac OS X Server, courtesy of Jeff_Sickel@sickel.com (2.2.5).

      Mac Rhapsody

      MPE IX 6.0

      NetBSD

      QNX RTP (QNX 6.0)

      Siemens Sinix

      UNICOS

      VMS 6.2, 7.1

      Windows NT IA64

5.1.  NT Porting Notes

  Always create tmp .bat file for actions if JAMSHELL is set.
  That way, if JAMSHELL is a .bat file itself, it can handle
  single-command actions with more than 9 cmd line args.

  COMSPEC is no longer examined: cmd.exe is always used
  instead.  Only cmd.exe can execute the Jambase rules anyhow.

  Jam can be built with Borland C++ 5.5.

  OS2 fixes: InstallBin now works.  Filenames are now downshifted,
  so mixed case works better there, too.  file_dirscan() can now scan
  the root ("c:\" or "\") directory, which it couldn't handle before.

  var_defines now ignores OS=Windows_NT, because it conflicts
  with Jam's setting of OS (to NT).

5.2. Mac OS 8/9 Notes

  The support for Mac is curious at best.  It runs under MPW.

  It requires CodeWarrior Pro 5, but no longer requires GUSI.

  Use Build.mpw to bootstrap the build.

  The Mac specific definitions in the Jambase are not intended
  to be of general purpose, but are sufficient to have Jam build
  itself.

===============================================================================
===============================================================================


Release Notes for Jam 2.2

1.  Release info:

  Jam 2.2
  October 22, 1997
  VERSION 2.2
  PATCHLEVEL 1

2. Compatibility

  Jam 2.2 is a roll-up of 'Jam - make(1) redux' release 2.1+.
  Most of the changes described below were available before this,
  in the jam.2.1.plus.tar ball.

  The Jam 2.2 language is a superset of the 2.1 language;
  Jamfiles, Jambase, and other rulesets used in 2.1 can be used
  with the 2.2 language support.

  See 'Jambase Changes', below, to see if your Jamfiles need any
  changes to work with the 2.2 Jambase.


3. Changes Since 2.1

  New product name: Jam. (Executable program is still named 'jam'.)

  Documentation rewritten; HTML versions supplied.


3.1 Changes to Jam Language

  Rules may now have more fields than just $(<) and $(>).

  Local variables are now supported.

  The expression 'if $(A) in $(B)' is now supported.

  New variable modifiers :U and :L result in uppercased or lowercased
  values.

  New variable modifier :P reliably results in parent directory
  of either a file or directory. (Previously, :D was used, but on VMS
  :D of a directory name is just the directory name.)

  The :S variable modifier now results in the _last_ suffix if a
  filename has more than one dot (.) in it.

  New predefined $(JAMDATE) variable is initialized at runtime for
  simple date stamping.

  New predefined variables $(OSVER) and $(OSPLAT) are used to
  distinguish among operating system versions and hardware platforms,
  when possible.

  New 'bind' qualifier on action definitions allows variables
  other than $(<) and $(>) to be bound with SEARCH and LOCATE paths.

  Action buffer size is no longer limited by MAXCMD. Instead, each
  line in an action is limited by MAXLINE, defined for each OS, and
  the entire action size is limited by CMDBUF.


3.2 Jambase Changes (See Jamfile.html)

  Jambase has been reworked to incorporate new language features.

  A handful of new utility rules has been added: makeString,
  makeDirName, etc.

  New HDRGRIST variable in Jambase allows for headers with the same
  name to be distinguished.

  LOCATE_TARGET now has a new flavor, LOCATE_SOURCE, that is used by
  rules that generate source files (e.g., Yacc and Lex).

  Header file includes now happen in the proper order. The limit of
  10 include files has been eliminated.

  The old "Install" rule is no longer available.  Use InstallBin,
  InstallFile, InstallLib, InstallMan, or InstallShell instead.


3.3 'jam' Changes (See Jam.html)

  'jam' can now be built as a stand-alone program, with Jambase
  compiled into the executable. An external or alternate Jambase can
  still be referenced explicitly with -f.

  On command failure, 'jam' now emits the text of the command that
  failed.  This is a compromise between the normal -d1 behavior (where
  commands were never seen) and -d2 (where commands are always seen).

  'jam' now exits non-zero if it doesn't have a total success.  A parse
  error, sources that can't be found, and targets that can't be built
  all generate non-zero exit status.

  The debugging levels (-d flags) have been slightly redefined.

  The supplied Jamfile now builds 'jam' into a platform specific
  subdirectory. This lets you use the same source directory to
  build 'jam' for more than one platform.

  The supplied Jamfile does not rebuild generated source files by
  default. (They are supplied with the distribution.) See Jamfile
  for more information.


4.  Fixed Bugs

  The 'include' bug has finally been fixed, so that include
  statements take effect exactly when they are executed,
  rather than after the current statement block.  This also
  corrects the problem where an 'include' within an 'if'
  block would wind up including the file one token after the
  'if' block's closing brace.  Credit goes to Thomas Woods
  for suggesting that the parse tree generation and parse
  tree execution be paired in their own loop, rather than
  having the parser execute the tree directly.

  The setting and extracting of grist has been regularized:
  normally, if you set a component of a filename (using the
  :DBSMG= modifiers), you are supposed to include the delimiters
  that set off the component:  that is, you say "$(x:S=.suffix)",
  including the ".".  But with grist it was inconsistent
  between setting and getting: setting grist required no
  <>'s, while getting grist included them.   Getting grist
  continues to return the <>'s, but now setting grist can
  either include them (the new way) or not (the old way).

  'actions together' now suppresses duplicate sources from
  showing up in $(>).

  Accessing variables whose names contained ['s (as happens with
  MkDir on VMS) wasn't working, because it treated the [ as an
  array subscript. Now [ and ] are, like :, handled specially so
  that they can appear in variable values.

  The 'if' statement now compares all elements in expressions;
  previously, it only compared the first element of each list.

  If a command line in an action is longer than MAXLINE (formerly
  MAXCMD), 'jam' now issues an error and exits rather than dumping
  core.

  If a Jamfile ended without a trailing newline, jam dumped core.
  This has been fixed.


5.  Porting

  See jam.h for the definitive list of supported platforms.
  Since 2.1, support has been added for:

      Macintosh MPW
      Alpha VMS
      Alpha NT
      NT PowerPC
      BeOS
      MVS OE
      UNIXWARE
      QNX
      SINIX (Nixdorf)
      OS/2
      Interactive UNIX (ISC), courtesy of Matthew Newhook


5.1 NT Support Fixes

  The NT command executor now handles multiple line actions, by writing
  multi-line actions to a batch file and executing that.

  Targets are universally lowercased on NT. (Matthew Newhook)

  Concurrent process support is fully enabled for NT.
  (Gurusamy Sarathy <gsar@engin.umich.edu>)

  Path handling: Jam now knows that the directory component of "D:\"
  is "D:\", just as on unix it knows that the directory component of
  "/" is "/".  It also now successfully gets the timestamp for "D:\"
  or just plain "\".


5.2 VMS Support Fixes

  VMS support is much, much better now.  The path name manipulation
  routines (in pathvms.c) were more or less rewritten, and they now
  handle the vagaries of combining directory and file names properly.

  Targets are universally lowercased on VMS.

  Multi-line command blocks on VMS are now executed in a single system()
  call rather than separate ones for each line, so that actions can
  be DCL scripts.

===============================================================================
===============================================================================


Release notes for Jam 2.1.

1.  Release info:
  Jam 2.1
  February 1, 1996
  VERSION 2.1
  PATCHLEVEL 0

2.  Porting

  Linux is now supported.

  FREEBSD is now supported.

  SCO ("M_XENIX") now supported.

  NCR now supported.

  NEXT support from karthy@dannug.dk (Karsten Thygesen)

  DECC support from zinser@axp614.gsi.de (Martin P.J. Zinser)

  I have changes for OS/2, but no way to test them.  Volunteers?
  I have VMS multiprocess support, but no way to test it.  Volunteers?

2.1.  NT Support fixes.

  The NT support is considerably more real than it was in 2.0.
  Filent.c had its syntax error corrected, it no longer skips the
  first entry when scanning directories, and it handles string
  tables in archives (for long object file names).

  The Jambase was changed a bit to support the various C/C++
  compilers on NT, although it has only been thorougly tested
  with MSVC20.

  You still need to set MSVCNT or BCCROOT to the root of the
  the compiler's directory tree, and you'll get an error if you
  don't set it (rather than getting a pile of mysterious errors).

2.2.  Other porting fixes.

  SPLITPATH now set up for UNIX (:), NT (;), VMS (,)

  Jambase support for Solaris works better now: the location of
  AR is hardwired to /usr/ccs/bin/ar and it knowns "install"
  doesn't take -c.  Solaris -- how the mighty have fallen.

  To handle Linux's wacko yacc, jamgram.h is now included after
  scan.h so that YYSTYPE is define.

3.  Jambase Changes (see Jamfile.html)

  SubDir now computes the root directory for the source tree, if
  the variable naming the root directory isn't set in the environment.
  It counts the number of directory elements leading from the root
  to the current directory (as passed to SubDir) and uses that many
  "../"'s to identify the root.  This means that to use SubDir you
  no longer have to have anything special set in the environment.

  InstallFile is now an alias for InstallLib.

  'first' is now dependency of all pseudo-targets (all, files,
  exe, lib, shell), so that jamming any of these pseudo-targets
  also builds any dependencies of 'first'.

  The File rule definition in the Jambase was missing an &.

  The File rule now calls the Clean rule, so that installed files
  get cleaned.

4.  Jam changes (see Jam.html)

  Variables may now be set on the command line with -svar=value.

  Targets marked with NOUPDATE are now immune to the -a (anyhow)
  flag.  Previously, the MkDir rule would try to recreate directories
  that already exist when jam was invoked with -a.

  A new variable, $(JAMVERSION), joins the small list of built-in
  variables.  It it set to the release of jam, currently "2.1".

  If an actions fails, jam now deletes the target(s).  It won't
  delete libraries or other targets that are composites.  This is
  now consistent with jam's behavior on interrupts (it deletes the
  targets).

  Jam had a nasty bug when setting multiple variables to the same
  value:  if the first two variable names were the same, the variable
  value got trashed.  This also affected "on target" variables if
  the first two targets were the same.  For example:

    FOO on bar.c bar.c foo.c = a b c ;

  This would mangle the value of FOO for bar.c and foo.c.  This has
  been fixed.

  Jam would generate bogus numbers when reporting the number of
  targets updated after an interrupt.  It now is more careful about
  counting.

  The debugging flag -d has been extended.  In addition to supporting
  -dx (turn on debugging for all levels up to x) there is also now
  -d+x (turn on debugging at only level x).  The default output
  level is -d1 (-or d2 if -n is given); this can be turned off with
  -d0.   The debug levels are listed in jam.1 and jam.h.

  The parsing debug output now uses indenting to indicate when
  one rule invokes another.

===============================================================================
===============================================================================


Release notes for Jam 2.0.

1.  Release info:
  Jam 2.0
  March 10, 1994
  VERSION 2.0
  PATCHLEVEL 5

2.  Porting

  Windows/NT is now (crudely) supported, courtesy of Brett Taylor
  and Laura Wingerd.

  COHERENT/386 is now supported, courtesy of Fred Smith.

  Solaris archive string table for long archive names is now
  supported, thanks to Mike Matrigali.

3.  Compatibility

  Jam 2.0 syntax is a superset of Jam 1.0 syntax, and thus it can
  interpret a Jam 1.0 Jambase.

  The Jam 2.0 Jambase is a superset of the Jam 1.0 Jambase, and
  thus it can include a Jamfile written for Jam 1.0.

4.  Changes from Jam 1.0 to Jam 2.0

4.1.  Documentation changes

  New Jamfile.5 manual page, with lots of examples and easy
  reading.  It replaces both the old "Examples" file as well as
  the old Jambase.5 manual page.

  jam.1 edited by Stephen W. Liddle and Diane Holt.

4.2.  Jambase Changes (see Jamfile.5)

4.2.1.  New rules:

  There are new rules to make handling subdirectories easier:
  SubDir, SubInclude, SubDirCcFlags, SubDirHdrs.

  There are new rules to handle file-specific CCFLAGS and HDRS:
  ObjectCcFlags and ObjectHdrs.

  Misc new rules: HardLink, InstallShell, MkDir.

  New rule "clean" that deletes exactly what jam has built, and
  "uninstall" that deletes exactly what was installed.

  New rules for handling suffixes .s, .f, .cc, .cpp, .C.

4.2.2.  Old rules:

  The InstallBin, Lib, Man, and the new Shell rules now take the
  destination directory as the target and the files to be copied
  as sources.  These rules formerly took the files to be copied
  as targets, and used built-in destination directories of
  $(BINDIR), $(LIBDIR), $(MANDIR), and $(BINDIR).

  The InstallBin, Lib, Man, and Shell rules use the install(1)
  program now, instead of doing their own copying.

  The Cc rule now uses -o when possible, rather than moving the
  result.  Some platforms (Pyramid?) have a broken -o.

  Jambase rules taking libraries, objects, and executables now
  all ignore the suffixes provided and use the one defined in the
  Jambase for the platform.

  Stupid yyacc support moved out of Jambase, as jam is its only
  likely user.

  Jambase now purturbs library sources with a "grist" of
  SOURCE_GRIST.

4.2.3.  Misc:

  The names of the default rules defined in Jambase have been
  lowercased and un-abbreviated, to be more imake(1) like.

  The Jambase has been reorganized and sorted, with VMS and NT
  support moved in from their own files.

  The Jambase has been relocated on UNIX from /usr/local/lib/jam
  to /usr/local/lib.

4.3.  Jam changes (see jam.1)

4.3.1.   Flags:

  New -a (anyhow) flag: means build everything.

  New -j<x> flag: run jobs in parallel.

  Old -t now rebuilds the touched target, rather that just the
  target's parents.

  -n now implies -d2, so that you see what's happening.  The
  debug level can be subsequently overridden.

  New -v to dump version.

4.3.2.  Rules:

  New ALWAYS rule behaves like -t: always builds target.

  New EXIT rule makes it possible to raise a fatal error.

  New LEAVES rule which say target depends only on the update
  times of the leaf sources.

  New NOUPDATE rule says built targets only if they don't exist.

  NOTIME has been renamed NOTFILE, to more accurately reflect its
  meaning (it says a target is not to be bound to a file).

4.3.3.  Variables:

  New special variable JAMSHELL: argv template for command execution
  shell.

  Variables, both normal and target-specific, can have their
  value appended with the syntax "var += value" or "var on target
  += value".

  "?=" is now synonymous with "default =".

  Imported enviroment variable values are now split at blanks
  (:'s if the variable name ends in PATH), so that they become
  proper list values.

4.3.4.  Misc:

  Files to be sourced with "include" are now bound first, so
  $(SEARCH) and $(LOCATE) affect them.  They still can't be
  built, though.

  New modifier on "actions": "existing" causes $(>) to expand
  only those files that currently exist.

4.3.5.  Bug fixes:

  When scanning tokens known to be argument lists (such as the
  arguments to rule invocations and variable assignment), the
  parser now tells the scanner to ignore alphabetic keywords, as
  all such lists terminate with punctuation keywords (like : or
  ;).  This way, alphabetic keywords don't need to be quoted when
  they appear as arguments.

  The scanner has been fixed to handle oversized tokens,
  unterminated quotes, unterminated action blocks, and tokens
  abutting EOF (i.e. a token with no white space before EOF).

  The progress report "...on xth target..." used to count all
  targets, rather than just those with updating actions.  Since
  the original pronouncement of targets to be udpated included
  only those with updating actions, the progress report has been
  changed to match.

  'If' conditionals now must be single arguments.  Previously,
  they could be zero or more arguments, which didn't make much
  sense, and made things like 'foo == bar' true.  The comparison
  operator is '=', and '==' just looked like the second of three
  arguments in the unary "non-empty argument list" conditional.

  Header files indirectly including themselves were mistakenly
  reported as being dependent on themselves.  Recursing through
  header file dependencies is now done after determining the fate
  of the target.

  The variable expansion support was expanding $(X)$(UNDEF) as if
  it were $(X).  It now expands to an empty list, like it
  should.

  The UNIX version of file_build() didn't handle "dir/.suffix"
  right.  Now it does.

  The VMS command buffer was assumed to be as large as 1024 bytes,
  which isn't the case everywhere as it is related to some weird
  quota.  It has been lowered to 256.

  $(>) and $(<) wouldn't expand in action blocks if the targets
  were marked with NOTIME.  Now they expand properly.

  Malloc() return values are now checked.

  The variable expansion routine var_expand() is now a little
  faster, by taking a few often needed shortcuts.

  The VMS version of file_build() used the wrong length when
  re-rooting file names that already had directory compoents.
  This was fixed.

  Various tracing adjustments were made.

5.  Limitations/Known Bugs

  The new Windows/NT support has only been marginally tested.  It
  is dependent on certain variables being set depending on which
  compiler you are using.  You'll need to look in the file
  Jambase and see what variables are expected to be set.

  The VMS support has been tested, courtesy of the DEC guest
  machine, but has not been hammered fully in release 2.0.  It
  was used quite a bit in Jam 1.0.

  Jam clean when there is nothing to clean claims it is updating
  a target.

  Because the include statement works by pushing a new file in
  the input stream of the scanner rather than recursively
  invoking the parser on the new file, multiple include
  statements in a rule's procedure causes the files to be
  included in reverse order.

  If the include statement appears inside an if block, the
  parser's attempt to find the else will cause the text of the
  included file to appear after the first token following the
  statement block.  This is rarely what is intended.

  In a rule's actions, only $(<) and $(>) refer to the bound file
  names:  all other variable references get the unbound names.
  This is a pain for $(NEEDLIBS), because it means that library
  path can't be bound using $(SEARCH) and $(LOCATE).

  With the -j flag, errors from failed commands can get
  staggeringly mixed up.  Also, because targets tend to get built
  in a quickest-first ordering, dependency information must be
  quite exact.  Finally, beware of parallelizing commands that
  drop fixed-named files into the current directory, like yacc(1)
  does.

  A poorly set $(JAMSHELL) is likely to result in silent
  failure.