The attributes changes were left out of Clang 17.
Attributes that used to take a string literal now accept an unevaluated
string literal instead, which means they reject numeric escape sequences
and strings literal with an encoding prefix - but the later was already
ill-formed in most cases.
We need to know that we are going to parse an unevaluated string literal
before we do - so we can reject numeric escape sequence,
so we derive from Attrs.td which attributes parameters are expected
to be string literals.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D156237
The swift_bridge attribute warns when the attribute is applied multiple
times to the same declaration. However, it warns about the arguments
being different to the attribute without ever checking if the arguments
actually are different. If the arguments are different, diagnose,
otherwise silently accept the code. Either way, drop the duplicated
attribute.
This extends semantic analysis of attributes for Swift interoperability
by introducing the `swift_bridge` attribute. This attribute enables
bridging Objective-C types to Swift specific types.
This is based on the work of the original changes in
8afaf3aad2
Differential Revision: https://reviews.llvm.org/D87532
Reviewed By: Aaron Ballman
