[PATCH] D150797: Turn unreachable error into assert

[Thomas Preud'homme via Phabricator via llvm-commits]

thopre added inline comments.


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Comment at: llvm/lib/FileCheck/FileCheck.cpp:148-150
   bool MissingFormPrefix = AlternateForm && !StrVal.consume_front("0x");
+  (void)MissingFormPrefix;
+  assert(!MissingFormPrefix && "missing alternate form prefix");
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jhenderson wrote:
> thopre wrote:
> > jhenderson wrote:
> > > I'd get rid of the unnecessary temporary and just do the calculation inline.
> > > 
> > > Also, is this the right place for the assert? Previously the error was later in the code.
> > Will the consume_front() happen if it's inside the assert though? Because under normal circumstances (i.e. assert does not trip) the consume_front() *must* happen for the function to do the right thing.
> Bleh, I missed that `consume_front` has side effects beyond getting the return value. Okay, I can't think of any real improvements (other than I think `static_cast` is preferred generally to C-style casts).
I agree in the general case but there is not a single use of static_cast<void> to indicate a function return value being ignored in the llvm/ subtree. There is however plenty of (void) C-style cast example. Ok to land as is?


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  https://reviews.llvm.org/D150797/new/

https://reviews.llvm.org/D150797