[PATCH] D150843: [clang][Diagnostics] Refactor printableTextForNextCharacter

[Timm Bäder via Phabricator via cfe-commits]

tbaeder added inline comments.


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Comment at: clang/lib/Frontend/TextDiagnostic.cpp:121
+  unsigned CharSize = llvm::getNumBytesForUTF8(*Begin);
+  const unsigned char *End = Begin + CharSize;
 
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tahonermann wrote:
> This could assign `End` to a location past the end of the source line when the source line ends with an ill-formed code unit sequence (e.g., a truncated 4-byte sequence). Constructing such a pointer is likely to get one in trouble.
If we use `bytes_end()` (unconditionally) we will check the entire source line every time we call this function (which always happens in a loop), which is what I was trying to avoid.


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  https://reviews.llvm.org/D150843/new/

https://reviews.llvm.org/D150843