Specifically, warn if:
* we find a character that the language standard says we must treat as an
identifier, and
* that character is not reasonably an identifier character (it's a punctuation
character or similar), and
* it renders identically to a valid non-identifier character in common
fixed-width fonts.
Some tools "helpfully" substitute the surprising characters for the expected
characters, and replacing semicolons with Greek question marks is a common
"prank".
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@320697 91177308-0d34-0410-b5e6-96231b3b80d8
This allows people to use Unicode in their #pragma mark and in macros
that exist only to be string-ized.
<rdar://problem/13107323&13121362>
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174081 91177308-0d34-0410-b5e6-96231b3b80d8
People use the C preprocessor for things other than C files. Some of them
have Unicode characters. We shouldn't warn about Unicode characters
appearing outside of identifiers in this case.
There's not currently a way for the preprocessor to tell if it's in -E mode,
so I added a new flag, derived from the PreprocessorOutputOptions. This is
only used by the Unicode warnings for now, but could conceivably be used by
other warnings or even behavioral differences later.
<rdar://problem/13107323>
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173881 91177308-0d34-0410-b5e6-96231b3b80d8
Richard Smith