sgatev added inline comments.

================
Comment at: clang/lib/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.cpp:78
+/// and integers in the framework.
+static const Expr *ignoreParenImpCastsExceptToBool(const Expr *E) {
+  const Expr *LastE = nullptr;
----------------
xazax.hun wrote:
> li.zhe.hua wrote:
> > sgatev wrote:
> > > I don't recall why we need to ignore implicit casts here. Can't we ignore 
> > > parens and rely on the built-in transfer function, possibly adding 
> > > handling of some missing casts there? 
> > > https://github.com/llvm/llvm-project/blob/main/clang/lib/Analysis/FlowSensitive/Transfer.cpp#L192
> > If we only ignore parens, a test in the optional checker tests begins to 
> > fail, specifically `UncheckedOptionalAccessTest.ValueOrComparison`. The 
> > missing "cast" is an `ExprWithCleanups`. I didn't know how to deal with 
> > that, so this patch just working around the assert.
> In general, I prefer to handle as much as possible with transfer functions 
> and skip as little as possible in the AST. We might skip `ExprWithCleanups` 
> nodes today, but we will need them tomorrow to properly model where certain 
> destructors are being invoked. 
We already have `skipExprWithCleanups` [1]. I wonder if it makes sense to 
replace that with a simple transfer function like the one for the `CK_NoOp` 
implicit cast. Would that solve the problem and remove the need for 
`ignoreParenImpCastsExceptToBool`? In the future we might replace that transfer 
function with a proper one, as Gábor suggested.

[1] 
https://github.com/llvm/llvm-project/blob/main/clang/lib/Analysis/FlowSensitive/Transfer.cpp#L36


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D124807/new/

https://reviews.llvm.org/D124807

_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits

Reply via email to