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Re: [Patch] Remove gccbug from bugreport.texi, take 3

> The original patch was described in terms of "deprecate its use right
> away".  I'd consider reasonable a patch that doesn't attempt to discuss
> preferences between bug reporting methods, but rather removes the
> discussion of particular methods from bugreport.texi.  That is, removes
> the whole section with discussion of gccbug, and with it the specific
> mention of GNATS, and changes the "Where to Report Bugs" section, removing
> mention of the mailing lists and making the total contents of that section 
> something like:
>   Please read @uref{} for bug reporting
>   instructions before you post a bug report.  A copy of this file is
>   included with GCC releases.

OK, thanks for the suggestion. I read to through the entire bug reporting
section of bugreport.texi, and in my view all that's there is also in
bugs.html, and in particular is more concise and less verbose than here.  
Some things are not up-to-date, for example that reports should be sent to
the mailing lists. So I just ripped most of it out. I don't think there's
anything in particular which needs to be taken over to bugs.html.

So is the following something that people would like?


Index: bugreport.texi
RCS file: /cvsroot/gcc/gcc/gcc/doc/bugreport.texi,v
retrieving revision 1.4
diff -c -r1.4 bugreport.texi
*** bugreport.texi	11 Apr 2003 21:34:57 -0000	1.4
--- bugreport.texi	13 May 2003 21:31:23 -0000
*** 29,42 ****
  * Criteria:  Bug Criteria.   Have you really found a bug?
- * Where: Bug Lists.	     Where to send your bug report.
  * Reporting: Bug Reporting.  How to report a bug effectively.
- * GNATS: gccbug.             You can use a bug reporting tool.
  * Known: Trouble.            Known problems.
  * Help: Service.             Where to ask for help.
  @end menu
! @node Bug Criteria,Bug Lists,,Bugs
  @section Have You Found a Bug?
  @cindex bug criteria
--- 29,40 ----
  * Criteria:  Bug Criteria.   Have you really found a bug?
  * Reporting: Bug Reporting.  How to report a bug effectively.
  * Known: Trouble.            Known problems.
  * Help: Service.             Where to ask for help.
  @end menu
! @node Bug Criteria,Bug Reporting,,Bugs
  @section Have You Found a Bug?
  @cindex bug criteria
*** 99,391 ****
  suggestions for improvement of GCC are welcome in any case.
  @end itemize
! @node Bug Lists,Bug Reporting,Bug Criteria,Bugs
! @section Where to Report Bugs
! @cindex bug report mailing lists
! @kindex or
! Send bug reports for the GNU Compiler Collection to
! @email{}.  In accordance with the GNU-wide
! convention, in which bug reports for tool ``foo'' are sent
! to @samp{}, the address @email{}
! may also be used; it will forward to the address given above.
! Please read @uref{} for additional and/or
! more up-to-date bug reporting instructions before you post a bug report.
! @node Bug Reporting,gccbug,Bug Lists,Bugs
! @section How to Report Bugs
  @cindex compiler bugs, reporting
! The fundamental principle of reporting bugs usefully is this:
! @strong{report all the facts}.  If you are not sure whether to state a
! fact or leave it out, state it!
! Often people omit facts because they think they know what causes the
! problem and they conclude that some details don't matter.  Thus, you might
! assume that the name of the variable you use in an example does not matter.
! Well, probably it doesn't, but one cannot be sure.  Perhaps the bug is a
! stray memory reference which happens to fetch from the location where that
! name is stored in memory; perhaps, if the name were different, the contents
! of that location would fool the compiler into doing the right thing despite
! the bug.  Play it safe and give a specific, complete example.  That is the
! easiest thing for you to do, and the most helpful.
! Keep in mind that the purpose of a bug report is to enable someone to
! fix the bug if it is not known.  It isn't very important what happens if
! the bug is already known.  Therefore, always write your bug reports on
! the assumption that the bug is not known.
! Sometimes people give a few sketchy facts and ask, ``Does this ring a
! bell?''  This cannot help us fix a bug, so it is basically useless.  We
! respond by asking for enough details to enable us to investigate.
! You might as well expedite matters by sending them to begin with.
! Try to make your bug report self-contained.  If we have to ask you for
! more information, it is best if you include all the previous information
! in your response, as well as the information that was missing.
! Please report each bug in a separate message.  This makes it easier for
! us to track which bugs have been fixed and to forward your bugs reports
! to the appropriate maintainer.
! To enable someone to investigate the bug, you should include all these
! things:
! @itemize @bullet
! @item
! The version of GCC@.  You can get this by running it with the
! @option{-v} option.
! Without this, we won't know whether there is any point in looking for
! the bug in the current version of GCC@.
! @item
! A complete input file that will reproduce the bug.  If the bug is in the
! C preprocessor, send a source file and any header files that it
! requires.  If the bug is in the compiler proper (@file{cc1}), send the
! preprocessor output generated by adding @option{-save-temps} to the
! compilation command (@pxref{Debugging Options}).  When you do this, use
! the same @option{-I}, @option{-D} or @option{-U} options that you used in
! actual compilation.  Then send the @var{input}.i or @var{input}.ii files
! generated.
! A single statement is not enough of an example.  In order to compile it,
! it must be embedded in a complete file of compiler input; and the bug
! might depend on the details of how this is done.
! Without a real example one can compile, all anyone can do about your bug
! report is wish you luck.  It would be futile to try to guess how to
! provoke the bug.  For example, bugs in register allocation and reloading
! frequently depend on every little detail of the function they happen in.
! Even if the input file that fails comes from a GNU program, you should
! still send the complete test case.  Don't ask the GCC maintainers to
! do the extra work of obtaining the program in question---they are all
! overworked as it is.  Also, the problem may depend on what is in the
! header files on your system; it is unreliable for the GCC maintainers
! to try the problem with the header files available to them.  By sending
! CPP output, you can eliminate this source of uncertainty and save us
! a certain percentage of wild goose chases.
! @item
! The command arguments you gave GCC to compile that example
! and observe the bug.  For example, did you use @option{-O}?  To guarantee
! you won't omit something important, list all the options.
! If we were to try to guess the arguments, we would probably guess wrong
! and then we would not encounter the bug.
! @item
! The type of machine you are using, and the operating system name and
! version number.
! @item
! The operands you gave to the @code{configure} command when you installed
! the compiler.
! @item
! A complete list of any modifications you have made to the compiler
! source.  (We don't promise to investigate the bug unless it happens in
! an unmodified compiler.  But if you've made modifications and don't tell
! us, then you are sending us on a wild goose chase.)
! Be precise about these changes.  A description in English is not
! enough---send a context diff for them.
! Adding files of your own (such as a machine description for a machine we
! don't support) is a modification of the compiler source.
! @item
! Details of any other deviations from the standard procedure for installing
! GCC@.
! @item
! A description of what behavior you observe that you believe is
! incorrect.  For example, ``The compiler gets a fatal signal,'' or,
! ``The assembler instruction at line 208 in the output is incorrect.''
! Of course, if the bug is that the compiler gets a fatal signal, then one
! can't miss it.  But if the bug is incorrect output, the maintainer might
! not notice unless it is glaringly wrong.  None of us has time to study
! all the assembler code from a 50-line C program just on the chance that
! one instruction might be wrong.  We need @emph{you} to do this part!
! Even if the problem you experience is a fatal signal, you should still
! say so explicitly.  Suppose something strange is going on, such as, your
! copy of the compiler is out of synch, or you have encountered a bug in
! the C library on your system.  (This has happened!)  Your copy might
! crash and the copy here would not.  If you @i{said} to expect a crash,
! then when the compiler here fails to crash, we would know that the bug
! was not happening.  If you don't say to expect a crash, then we would
! not know whether the bug was happening.  We would not be able to draw
! any conclusion from our observations.
! If the problem is a diagnostic when compiling GCC with some other
! compiler, say whether it is a warning or an error.
! Often the observed symptom is incorrect output when your program is run.
! Sad to say, this is not enough information unless the program is short
! and simple.  None of us has time to study a large program to figure out
! how it would work if compiled correctly, much less which line of it was
! compiled wrong.  So you will have to do that.  Tell us which source line
! it is, and what incorrect result happens when that line is executed.  A
! person who understands the program can find this as easily as finding a
! bug in the program itself.
! @item
! If you send examples of assembler code output from GCC,
! please use @option{-g} when you make them.  The debugging information
! includes source line numbers which are essential for correlating the
! output with the input.
! @item
! If you wish to mention something in the GCC source, refer to it by
! context, not by line number.
! The line numbers in the development sources don't match those in your
! sources.  Your line numbers would convey no useful information to the
! maintainers.
! @item
! Additional information from a debugger might enable someone to find a
! problem on a machine which he does not have available.  However, you
! need to think when you collect this information if you want it to have
! any chance of being useful.
! @cindex backtrace for bug reports
! For example, many people send just a backtrace, but that is never
! useful by itself.  A simple backtrace with arguments conveys little
! about GCC because the compiler is largely data-driven; the same
! functions are called over and over for different RTL insns, doing
! different things depending on the details of the insn.
! Most of the arguments listed in the backtrace are useless because they
! are pointers to RTL list structure.  The numeric values of the
! pointers, which the debugger prints in the backtrace, have no
! significance whatever; all that matters is the contents of the objects
! they point to (and most of the contents are other such pointers).
! In addition, most compiler passes consist of one or more loops that
! scan the RTL insn sequence.  The most vital piece of information about
! such a loop---which insn it has reached---is usually in a local variable,
! not in an argument.
! @findex debug_rtx
! What you need to provide in addition to a backtrace are the values of
! the local variables for several stack frames up.  When a local
! variable or an argument is an RTX, first print its value and then use
! the GDB command @code{pr} to print the RTL expression that it points
! to.  (If GDB doesn't run on your machine, use your debugger to call
! the function @code{debug_rtx} with the RTX as an argument.)  In
! general, whenever a variable is a pointer, its value is no use
! without the data it points to.
! @end itemize
! Here are some things that are not necessary:
! @itemize @bullet
! @item
! A description of the envelope of the bug.
! Often people who encounter a bug spend a lot of time investigating
! which changes to the input file will make the bug go away and which
! changes will not affect it.
! This is often time consuming and not very useful, because the way we
! will find the bug is by running a single example under the debugger with
! breakpoints, not by pure deduction from a series of examples.  You might
! as well save your time for something else.
! Of course, if you can find a simpler example to report @emph{instead} of
! the original one, that is a convenience.  Errors in the output will be
! easier to spot, running under the debugger will take less time, etc.
! Most GCC bugs involve just one function, so the most straightforward
! way to simplify an example is to delete all the function definitions
! except the one where the bug occurs.  Those earlier in the file may be
! replaced by external declarations if the crucial function depends on
! them.  (Exception: inline functions may affect compilation of functions
! defined later in the file.)
! However, simplification is not vital; if you don't want to do this,
! report the bug anyway and send the entire test case you used.
! @item
! In particular, some people insert conditionals @samp{#ifdef BUG} around
! a statement which, if removed, makes the bug not happen.  These are just
! clutter; we won't pay any attention to them anyway.  Besides, you should
! send us cpp output, and that can't have conditionals.
! @item
! A patch for the bug.
! A patch for the bug is useful if it is a good one.  But don't omit the
! necessary information, such as the test case, on the assumption that a
! patch is all we need.  We might see problems with your patch and decide
! to fix the problem another way, or we might not understand it at all.
! Sometimes with a program as complicated as GCC it is very hard to
! construct an example that will make the program follow a certain path
! through the code.  If you don't send the example, we won't be able to
! construct one, so we won't be able to verify that the bug is fixed.
! And if we can't understand what bug you are trying to fix, or why your
! patch should be an improvement, we won't install it.  A test case will
! help us to understand.
! See @uref{}
! for guidelines on how to make it easy for us to
! understand and install your patches.
! @item
! A guess about what the bug is or what it depends on.
! Such guesses are usually wrong.  Even I can't guess right about such
! things without first using the debugger to find the facts.
! @item
! A core dump file.
! We have no way of examining a core dump for your type of machine
! unless we have an identical system---and if we do have one,
! we should be able to reproduce the crash ourselves.
! @end itemize
! @node gccbug,, Bug Reporting, Bugs
! @section The gccbug script
! @cindex gccbug script
! To simplify creation of bug reports, and to allow better tracking of
! reports, we use the GNATS bug tracking system.  Part of that system is
! the @command{gccbug} script.  This is a Unix shell script, so you need a
! shell to run it.  It is normally installed in the same directory where
! @command{gcc} is installed.
! The gccbug script is derived from send-pr, @pxref{using
! send-pr,,Creating new Problem Reports,send-pr,Reporting Problems}.  When
! invoked, it starts a text editor so you can fill out the various fields
! of the report.  When the you quit the editor, the report is automatically
! send to the bug reporting address.
! A number of fields in this bug report form are specific to GCC, and are
! explained at @uref{}.
--- 97,107 ----
  suggestions for improvement of GCC are welcome in any case.
  @end itemize
! @node Bug Reporting,Trouble,Bug Criteria,Bugs
! @section How and where to Report Bugs
  @cindex compiler bugs, reporting
! Bugs should be reported to our bug database.  Please refer to
! @uref{} for up-to-date instructions how to
! submit bug reports.  A copy of this file should also be part of the
! documentation thath comes with GCC releases.

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