[PATCH] D77809: [Analyzer] Include typedef statements in CFG build.

[Gábor Horváth via Phabricator via cfe-commits]

xazax.hun added inline comments.


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Comment at: clang/lib/Analysis/CFG.cpp:2855
+
   VarDecl *VD = dyn_cast<VarDecl>(DS->getSingleDecl());
 
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balazske wrote:
> Szelethus wrote:
> > How about `using`? How about some other shenanigans that obscure the size of the VLA? Can't we just retrieve the size from `VariableArrayType::getSizeExpr` after seeing this `VarDecl`, and add that to the block?
> The current code does that, it gets the size with `getSizeExpr` and adds it. The loop is needed to support multiple array dimensions.
> 
> To support every other type that can contain VLA a similar code is needed as in `CodeGenFunction::EmitVariablyModifiedType` (go over the type chain and look not only for `VariableArrayType`). The current code works only if there is typedef (or type alias) with a plain VLA, maybe embedded into another.
> If support for every other case is needed, it is a change on its own because the code that generates CFG for VLA declaration is wrong too (later in the same function, the new code is copied from that). For example `void (*vla)(int[x]);` does not work now (`x` is not included in CFG). This is better to do in a later patch, for now this more restricted functionality is better than nothing (it is not wrong, only do not support all, probably seldom used, cases).
I'd prefer to have some FIXME comments in this patch to document what is missing. Moreover, it would be great to have a test case for `void (*vla)(int[x]);` with a similar FIXME comment of the expected behavior. 


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D77809/new/

https://reviews.llvm.org/D77809