Re: Clang 3.3 Analyzer Results

On 2013-11-12 15:33:13 -0500, Jeffrey Walton wrote:
> On Tue, Nov 12, 2013 at 3:25 PM, Andres Freund <andres@2ndquadrant.com> wrote:
> > On 2013-11-12 15:17:18 -0500, Jeffrey Walton wrote:
> >> On Tue, Nov 12, 2013 at 9:38 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >> > ...
> >> > One thought for the Clang people is that most of the reports such as "null
> >> > pointer dereference" presumably mean "I think I see an execution path
> >> > whereby we could get here with a null pointer".  If so, it'd be awfully
> >> > helpful if the complaint included some description of what that path is.
> >> > I think Coverity does that, or at least I've seen output from some tool
> >> > that does it.
> >> Clang can be trained with asserts.
> >
> > It might not recognize our Assert() because it expands as:
> > #define TrapMacro(condition, errorType) \
> >         ((bool) ((! assert_enabled) || ! (condition) || \
> >                          (ExceptionalCondition(CppAsString(condition), (errorType), \
> >                                                                    __FILE__, __LINE__), 0)))
> >
> > #define Assert(condition) \
> >                 Trap(!(condition), "FailedAssertion")
> >
> > Kevin, perhaps it reports less errors if you remove the assert_enabled
> > check from TrapMacro? I guess you already compiled with --enable-cassert?

> Also see http://clang-analyzer.llvm.org/annotations.html (ignore the
> OS X specific stuff). There's a couple of ways to annotate source code
> and custom asserts. In this case, a `noreturn` annotation will
> probably do the trick.

ExceptionalCondition is annotated with noreturn, but that doesn't
necessarily help because the compiler cannot know that assert_enabled is
true.

Greetings,

Andres Freund

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