gdb/doc/snapshots.readme

   1                          GDB SNAPSHOT SYSTEM
   2                             (general info)
   3                            Updated 8/23/93
   4
   5 WHAT ARE GDB SNAPSHOTS
   6 ----------------------
   7
   8 Snapshots are an "image" of the main GDB development tree, captured at a
   9 particular random instant in time.  When you use the snapshots, you should be
  10 able to maintain a local copy of GDB that is no more than one day older than
  11 the official source tree used by the GDB maintainers.
  12
  13 The primary purpose of providing snapshots is to widen the group of motivated
  14 developers that would like to help test, debug, and enhance GDB, by providing
  15 you with access to the "latest and greatest" source.  This has several
  16 advantages, and several disadvantages.
  17
  18     First the advantages:
  19
  20     o   Once we have a large base of motivated testers using the snapshots,
  21         this should provide good coverage across all currently supported
  22         GDB hosts and targets.  If a new bug is introduced in GDB due to
  23         fixing another bug or ongoing development, it should become
  24         obvious much more quickly and get fixed before the next general
  25         net release.  This should help to reduce the chances of GDB being
  26         released to the general public with a major bug that went unnoticed
  27         during the release cycle testing because they are machine dependent.
  28         We hope to greatly improve GDB's stability and reliability by
  29         involving more people and more execution environments in the
  30         prerelease testing.
  31
  32     o   With access to the latest source, any diffs that you send to fix
  33         bugs or add new features should be much easier for the GDB team
  34         to merge into the official source base (after suitable review
  35         of course).  This encourages us to merge your changes quicker,
  36         while they are still "fresh".
  37
  38     o   Once your diffs are merged, you can obtain a new copy of GDB
  39         containing your changes almost immediately.  Thus you do not
  40         have to maintain local copies of your changes for any longer
  41         than it takes to get them merged into the official source base.
  42         This encourages you to send in changes quicker.
  43
  44     And the disadvantages:
  45
  46     o   The snapshot you get will be largely untested and of unknown quality.
  47         It may fail to configure or compile.  It may have serious bugs.
  48         You should always keep a copy of the last known working version
  49         before updating to the current snapshot, or at least be able to
  50         regenerate a working version if the latest snapshot is unusable
  51         in your environment for some reason.
  52
  53         If a production version of GDB has a bug and a snapshot has the fix,
  54         and you care about stability, you should put only the fix for that
  55         particular problem into your production version.  Of course, if you
  56         are eager to test GDB, you can use the snapshot versions in your
  57         daily work, but users who have not been consulted about whether they
  58         feel like testing GDB should generally have something which is at
  59         least as bug free as the last released version.
  60
  61     o   Providing timely response to your questions, bug reports, and
  62         submitted patches will require the GDB development team to allocate
  63         time from an already thin time budget.  Please try to help us make
  64         this time as productive as possible.  See the section below about
  65         how to submit changes.
  66
  67
  68 HOW TO GET THE SNAPSHOTS
  69 ------------------------
  70
  71 The current plan is to provide a full snapshot daily, so that users getting a
  72 snapshot for the first time, or updating after a long period of not updating,
  73 can get the latest version in a single operation.  Along with the full
  74 snapshot, we will provide incremental diffs on a daily basis.  Each daily diff
  75 will be relative to the source tree after applying all previous daily diffs.
  76 The daily diffs are for people who have relatively low bandwidth ftp or uucp
  77 connections.
  78
  79 The files will be available via anonymous ftp from ftp.cygnus.com, in
  80 directory pub/gdb, and should look something like:
  81
  82         gdb-930401.tar.z
  83         gdb-930401-930402.diff.z
  84         gdb-930402-930403.diff.z
  85         gdb-930403-930404.diff.z
  86         .
  87         .
  88         .
  89
  90 At some point, the files should automatically appear during the evening as a
  91 result of an automatically run process each evening.  For the moment however,
  92 the process will be manually run by one of the gdb maintainers and the
  93 appropriate files moved to the ftp area at some convenient point during the
  94 day.
  95
  96 Note that the current plan is to provide GNU gzip compressed files only.  You
  97 can ftp gzip from prep.ai.mit.edu in directory pub/gnu.
  98
  99 Also, even though we will make the snapshots available on a publically
 100 accessible ftp area, we ask that recipients not widely publicise their
 101 availability.  The motivation for this request is not to hoard them, but to
 102 avoid the situation where the general GDB user base naively attempts to use
 103 the snapshots, has trouble with them, complains publically, and the reputation
 104 of GDB suffers because of a perception of instability or lack of quality
 105 control.
 106
 107
 108 GDB TEST SUITE
 109 --------------
 110
 111 A test suite is distributed as an integral part of the snapshots.  However, to
 112 use it you will need to get a copy of the dejagnu testing framework.
 113 Snapshots of dejagnu are available alongside the GDB snapshots, using the same
 114 naming conventions as the GDB snapshots.  Once you have installed the dejagnu
 115 framework, a simple "make check" in the GDB directory should be sufficient to
 116 run the tests.
 117
 118 Note that the test suite is still in its infancy.  The test framework itself
 119 might not install on your system if you have an environment that is not
 120 similar to one that the GDB developers already use.  The tests themselves only
 121 cover a small portion of GDB features, and what tests do exist for a feature
 122 are not exhaustive.  New tests are welcomed.
 123
 124
 125 GETTING HELP, GDB DISCUSSIONS, etc
 126 ----------------------------------
 127
 128 Mail sent to gdb-testers@cygnus.com goes to everyone on the list of gdb
 129 testers, which should include everyone getting the gdb snapshots.  It is
 130 appropriate whenever you wish your mail to be seen by all the testers.  This
 131 would include announcements of any kind, notices of intent to implement a
 132 specific enhancement (to coordinate with other people on the list), etc.
 133 Before sending something to gdb-testers, ask yourself if what you are about to
 134 send would be something you would care to see show up in your mailbox if it
 135 was sent by someone else.
 136
 137 Mail sent to gdb-patches@cygnus.com goes to gdb support people internal to
 138 Cygnus.  Despite the name, it is appropriate for more than just patches.
 139 Questions about the snapshots, problems accessing the snapshots, bug reports
 140 without patches, requests for advice on how to track down a bug you have
 141 encountered, discussion about bug fixes or enhancements in progress, etc are
 142 all welcome in gdb-patches.  Usually mail sent to gdb-patches will result in a
 143 short private email discussion between you and one or more of the gdb
 144 developers who can assist you with simple questions or handle your patches.
 145 Note that gdb-patches is *not* a general gdb electronic support line.  If you
 146 are in need of such support, you probably should not be using the snapshots
 147 and should seek out one of the commercial suppliers of support for free
 148 software.
 149
 150 Do *not* send any questions about the snapshots or patches specific to the
 151 snapshots to bug-gdb@prep.ai.mit.edu (gateway'd to the usenet group
 152 gnu.gdb.bug).  Nobody there will have any idea what you are talking about and
 153 it will just cause confusion.
 154
 155
 156 BUG REPORTS
 157 -----------
 158
 159 Send bug reports to gdb-patches@cygnus.com.
 160
 161 Note that since no testing is done on the snapshots, and snapshots may even be
 162 made when gdb is in an inconsistent state, it may not be unusual for an
 163 occasional snapshot to have a very obvious bug, such as failure to compile on
 164 *any* machine.  It is likely that such bugs will be fixed by the next
 165 snapshot, so it really isn't necessary to report them unless they persist for
 166 a couple days.
 167
 168 Missing files should always be reported, since they usually mean there is a
 169 problem with the snapshot-generating process and we won't know about them
 170 unless someone tells us.
 171
 172 Bugs which are non-obvious, such as failure to compile on only a specific
 173 machine, a new machine dependent or obscure bug (particularly one not detected
 174 by the testsuite), etc should be reported when you discover them, or have a
 175 suggested patch to fix them.
 176
 177
 178 FORMAT FOR PATCHES
 179 ------------------
 180
 181 If you have a fix for a bug, or an enhancement to submit, send your patch to
 182 gdb-patches@cygnus.com.  Here are some simple guidelines for submitting
 183 patches:
 184
 185     o   Use "context diffs" for patches.  A typical command for generating
 186         context diffs is "diff -rc gdb-old gdb-new".
 187
 188     o   Use the "minimalist approach" for patches.  That is, each patch
 189         should address only one particular bug, new feature, etc.  Do not
 190         save up many unrelated changes and submit them all in one big
 191         patch, since in general, the larger the patch the more difficult
 192         it is for us to decide if the patch is either correct or
 193         desirable.  And if we find something about the patch that needs
 194         to be corrected before it can be installed, we would have to reject
 195         the entire patch, which might contain changes which otherwise would
 196         be accepted if submitted separately.
 197
 198     o   Submit a sample ChangeLog entry with your patch.  See the existing
 199         GDB ChangeLog for examples of what a ChangeLog entry should look
 200         like.  The emacs command ^X4A will create a ChangeLog entry header
 201         for you.
 202
 203
 204 BISON and BYACC
 205 ---------------
 206
 207 GDB's language parsers are all portable, and can be compiled with bison,
 208 byacc, traditional Unix yacc, or other compatible parser generators.  For
 209 various reasons, Cygnus uses byacc rather than bison by default.  When a
 210 general gdb distribution is made, this default is switched back to bison.  The
 211 snapshots follow the Cygnus default.  Your options, if you do not already have
 212 byacc installed, include:
 213
 214     o   Hack the upper level Makefile.in lines that look like:
 215
 216         BISON = `if [ -f $${rootme}/byacc/byacc ] ; \
 217                     then echo $${rootme}/byacc/byacc ; \
 218                     else echo byacc ; \                         <== change
 219                 fi`
 220
 221         to replace "byacc" with either "yacc" or "bison -y".
 222
 223     o   Fetch the byacc snapshot from the same location as the gdb snapshots
 224         and install byacc.
 225
 226     o   Specify BISON=yacc on the make command line to override the default.
 227
 228
 229 UNIX MAKE and GNU MAKE
 230 ----------------------
 231
 232 When you build gdb in the same directory as the source, you should be able to
 233 use any available "make" that has traditional UNIX make functionality.  If you
 234 build gdb in a separate directory tree from the source, using the configure
 235 "--srcdir" option, then only GNU make is fully supported, although other makes
 236 with complete VPATH support should work (SunOS make for example).
 237
 238
 239
 240 Thanks for your help and support.
 241
 242 -Fred Fish
 243  Cygnus Support