[PATCH] D64671: [clang-tidy] New check: misc-init-local-variables

[Jussi Pakkanen via Phabricator via cfe-commits]

jpakkane marked an inline comment as done.
jpakkane added inline comments.


================
Comment at: clang-tools-extra/clang-tidy/misc/InitLocalVariablesCheck.cpp:21
+  Finder->addMatcher(
+      varDecl(unless(hasInitializer(anything()))).bind("vardecl"), this);
+}
----------------
alexfh wrote:
> jpakkane wrote:
> > alexfh wrote:
> > > I believe, this should skip matches within template instantiations. Consider this code:
> > > ```
> > > template<typename T>
> > > void f(T) { T t; }
> > > void g() {
> > >     f(0);
> > >     f(0.0);
> > > }
> > > ```
> > > 
> > > What will the fix  be?
> > I tested with the following function:
> > 
> > 
> > ```
> > template<typename T>
> > void template_test_function() {
> >   T t;
> >   int uninitialized;
> > }
> > ```
> > 
> > Currently it warns on the "uninitialized" variable regardless of whether the template is instantiated or not. If you call it with an int type, it will warn about variable t being uninitialized. If you call it with a, say, struct type, there is no warnings. Is this a reasonable approach?
> And what happens, if there are multiple instantiations of the same template, each of them requiring a different fix? Can you try the check with my example above (and maybe also add `f("");`inside `g()`). I believe, the check will produce multiple warnings with conflicting fixes (and each of them will be wrong, btw).
Interestingly it does warn about it, but only once, even if you have two different template specializations.

I tried to suppress this warning when the type being instantiated is a template argument type but no matter what I tried I could not get this to work. Is there a way to get this information from the MatchedDecl object or does one need to do something more complicated like going up the AST until a function definition is found and checking if it is a template specialization (presumably with TemplatedKind)? Any help would be appreciated.


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  rCTE Clang Tools Extra

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https://reviews.llvm.org/D64671