16f6c0aecf
Inline adoc files when they are included exactly once. Also fix language tags because this inlining gives us better information on what language the code is written in.
130 lines
3.8 KiB
Plaintext
130 lines
3.8 KiB
Plaintext
== Why is this an issue?
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Empty declarations are cruft; they (may) compile, but they violate the language standards, don't contribute anything of value, and clutter up the program. Like cobwebs, they should be swept away.
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=== Noncompliant code example
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[source,cpp]
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----
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int; // Noncompliant
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----
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== Resources
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* ISO/IEC 9899:2011, 6.7p2
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* ISO/IEC 14882:2011, 7p3.
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* https://wiki.sei.cmu.edu/confluence/x/5dUxBQ[CERT, MSC12-C.] - Detect and remove code that has no effect or is never executed
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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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=== Message
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Remove this empty declaration.
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'''
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== Comments And Links
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(visible only on this page)
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=== on 24 Mar 2015, 19:03:23 Evgeny Mandrikov wrote:
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\[~ann.campbell.2] we could also add that this actually violates restrictions in standard - see C11 6.7p2 and CPP11 7p3, but might be accepted by compilers.
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=== on 24 Mar 2015, 19:32:50 Ann Campbell wrote:
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Added [~evgeny.mandrikov]. Is there an officially hosted copy of the language standards we can link to?
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=== on 24 Mar 2015, 22:07:05 Evgeny Mandrikov wrote:
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\[~ann.campbell.2] ISO standards are paid.
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=== on 25 Mar 2015, 13:04:35 Ann Campbell wrote:
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One more question [~evgeny.mandrikov] is C11 the full, official name of the standard? Should I throw "ISO" in there?
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=== on 25 Mar 2015, 18:08:20 Evgeny Mandrikov wrote:
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\[~ann.campbell.2] according to \http://en.wikipedia.org/wiki/C%2B%2B - "{cpp}11" is informal name for "ISO/IEC 14882:2011", "CPP11" - is a name, which we use in code to refer to it. Similarily for "C11" - \http://en.wikipedia.org/wiki/C11_(C_standard_revision).
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=== on 25 Mar 2015, 20:03:24 Ann Campbell wrote:
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Thanks [~evgeny.mandrikov]
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=== on 25 Mar 2015, 20:14:39 Evgeny Mandrikov wrote:
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\[~ann.campbell.2] however I'm not sure that usual developers know that "9899" refers to "C" and "14882" to "{cpp}" :) but that's probably not a problem, so overall LGTM.
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=== on 23 Nov 2015, 21:40:30 Ann Campbell wrote:
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\[~evgeny.mandrikov] I've just mapped this to PC-Lint rule 814
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____
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useless declaration -- A tagless struct was declared without a declarator. For example:
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----
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struct { int n; };
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----
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Such a declaration cannot very well be used.
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____
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Is that case already covered, or is a ticket needed?
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=== on 24 Nov 2015, 15:03:51 Evgeny Mandrikov wrote:
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\[~ann.campbell.2] I suppose that this case was not covered, but you can check by yourself ;)
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Also IMO such change requires more investigations, because:
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{noformat}
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struct {
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int i;
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};
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{noformat}
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gives warning ("declaration does not declare anything") with Clang in C mode and error ("anonymous structs and classes must be class members") in {cpp} mode, while no messages for
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{noformat}
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struct S {
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struct {
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int i; // can be accessed as "s.i"
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};
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} s;
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{noformat}
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which is probably related to \https://msdn.microsoft.com/en-us/library/a3bbz53t.aspx and \https://gcc.gnu.org/onlinedocs/gcc/Unnamed-Fields.html.
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And in any case seems that current rule description is not applicable for such case, because it doesn't violate standards.
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Also could be noted that seems that PC-Lint rule 814 available only for C.
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=== on 24 Nov 2015, 15:17:59 Ann Campbell wrote:
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\[~evgeny.mandrikov] you do realize you didn't actually answer the question, right? ;-)
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Should I unmap, or do you feel this case is worth covering?
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Re only-for-C, I had planned to follow up on that issue separately. In short: yes. I'm lazy.
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=== on 5 Feb 2016, 16:46:42 Evgeny Mandrikov wrote:
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\[~ann.campbell.2] my answer was - given current description I don't see why PC-Lint 814 maps to this RSPEC.
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=== on 5 Feb 2016, 17:02:00 Evgeny Mandrikov wrote:
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\[~ann.campbell.2] and to add a little bit more oil into fire of this discussion - some other cases in CPP-1371
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=== on 5 Feb 2016, 17:09:30 Ann Campbell wrote:
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unmapped
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endif::env-github,rspecator-view[]
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