[PATCH] D155610: [Clang][Sema] Fix display of characters on static assertion failure

[Corentin Jabot via Phabricator via cfe-commits]

cor3ntin added inline comments.


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Comment at: clang/test/SemaCXX/static-assert-cxx26.cpp:304
+static_assert('\u{9}' == (char)1, ""); // expected-error {{failed}} \
+                                       // expected-note {{evaluates to ''\t' (0x09, 9) == '<U+0001>' (0x01, 1)'}}
+static_assert((char8_t)-128 == (char8_t)-123, ""); // expected-error {{failed}} \
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tahonermann wrote:
> Is the expected note up to date? I don't see code that would generate the `<U+0001>` output. Am I just missing it? Since U+0001 is a valid, though non-printable, character, I would expect more `'\u0001'`.
See elsewhere in the discussion. this formating is pre existing and managed at the DiagnosticEngine level (pushEscapedString). the reason it's not `\u0001` is 1/ to avoid  reusing c++ syntactic elements for something that comes from diagnostics and is not represented as an escaped sequence in source 2/ `\u00011` is unreadable, and `\U000000001` is also not helpful :)



CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D155610/new/

https://reviews.llvm.org/D155610