Re: [wwwdocs] Add section on diagnostics conventions

[Diego Novillo <dnovillo at google dot com>]

On Mon, Jan 30, 2012 at 15:21, Joseph S. Myers <joseph@codesourcery.com> wrote:
> On Sun, 29 Jan 2012, Diego Novillo wrote:
>
>> +<li><code>internal_error</code> is used for conditions that should not
>> +be triggered by any user input whether valid or invalid and including
>> +invalid asms and LTO binary data (sometimes, as an exception, there is
>> +a call to <code>error</code> before further information is printed and
>> +an ICE is triggered).</li>
>> +
>> +<li>Assertion failures should not be triggered by invalid input.
>> +<code>inform</code> is for informative notes accompanying errors and
>> +warnings. All diagnostics should be full sentences without English
>> +fragments substituted in them, to facilitate translation.</li>
>
> The three sentences in this last list item are actually three independent
> and unrelated points. ÂI think the first one about assertion failures
> should be moved up into the previous list item, while the remaining two
> sentences should each be a list item on its own.

Thanks.  Fixed with the patch below.


Index: codingconventions.html
===================================================================
RCS file: /cvs/gcc/wwwdocs/htdocs/codingconventions.html,v
retrieving revision 1.63
diff -u -d -u -p -r1.63 codingconventions.html
--- codingconventions.html      12 Feb 2011 15:49:51 -0000      1.63
+++ codingconventions.html      1 Feb 2012 01:47:55 -0000
@@ -157,6 +157,47 @@ regression-checkers distinguish a true r
 to the test suite.</p>


+<h2>Diagnostics Conventions</h2>
+<ul>
+
+<li>Use of the <code>input_location</code> global, and of the
+diagnostic functions that implicitly use <code>input_location</code>,
+is deprecated; the preferred technique is to pass around locations
+ultimately derived from the location of some explicitly chosen source
+code token.</li>
+
+<li>Diagnostics using the GCC diagnostic functions should generally
+use the GCC-specific formats such as <code>%qs</code> or
+<code>%&lt;</code> and <code>%&gt;</code> for quoting and
+<code>%m</code> for <code>errno</code> numbers.</li>
+
+<li>Identifiers should generally be formatted with <code>%E</code> or
+<code>%qE</code>; use of <code>identifier_to_locale</code> is needed
+if the identifier text is used directly.</li>
+
+<li>Formats such as <code>%wd</code> should be used with types such as
+<code>HOST_WIDE_INT</code> (<code>HOST_WIDE_INT_PRINT_DEC</code> is a
+format for the host <code>printf</code> functions, not for the GCC
+diagnostic functions).</li>
+
+<li><code>error</code> is for defects in the user's code.</li>
+
+<li><code>internal_error</code> is used for conditions that should not
+be triggered by any user input whether valid or invalid and including
+invalid asms and LTO binary data (sometimes, as an exception, there is
+a call to <code>error</code> before further information is printed and
+an ICE is triggered).  Assertion failures should not be triggered by
+invalid input.</li>
+
+<li><code>inform</code> is for informative notes accompanying errors
+and warnings.</li>
+
+<li>All diagnostics should be full sentences without English
+fragments substituted in them, to facilitate translation.</li>
+
+</ul>
+
+
 <h2>Miscellaneous Conventions</h2>

 <p>Code should use <code>gcc_assert(EXPR)</code> to check invariants.