[PATCH] D55270: [Sema] Further improvements to to static_assert diagnostics.

[Clement Courbet via Phabricator via cfe-commits]

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


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Comment at: test/PCH/cxx-static_assert.cpp:17
 
-// expected-error at 12 {{static_assert failed "N is not 2!"}}
+// expected-error at 12 {{static_assert failed due to requirement '1 == 2' "N is not 2!"}}
 T<1> t1; // expected-note {{in instantiation of template class 'T<1>' requested here}}
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aaron.ballman wrote:
> I'm not certain how I feel about now printing the failure condition when there's an explicit message provided. From what I understand, a fair amount of code in the wild does `static_assert(some_condition, "some_condition")` because of older language modes where the message was not optional. I worry we're going to start seeing a lot of diagnostics like: `static_assert failed due to requirement '1 == 2' "N == 2"`, which seems a bit low-quality. See `DFAPacketizer::DFAPacketizer()` in LLVM as an example of something similar.
> 
> Given that the user entered a message, do we still want to show the requirement? Do we feel the same way if the requirement is fairly large?
The issue is that `"N == 2"` is a useless error message. Actually, since the  error message has to be a string literal, there is no way for the user to print a debuggable output. So I really think we should print the failed condition.


Repository:
  rC Clang

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  https://reviews.llvm.org/D55270/new/

https://reviews.llvm.org/D55270