Importing a non-library-evolution enabled module from a
library-evolution enabled module will lead to generating a
swiftinterface that can't be rebuilt by a different compiler.
Make it a hard error when using access level imports, and keep it as a
warning for @_implementationOnly imports.
When targeting Swift 5 and earlier, the default import is public. To
notify of a possible unintentional public import, raise errors on
default imports when other imports of the same target have an explicit
type.
This check isn't necessary in the tentative Swift 6 mode.
Per the current proposal, these are to be specified
explicitly, as they form an important part of the API.
Bonus: This commit includes a fix to make
`CompileTimeConstTypeRepr` a proper `isa<>` subtype of
`SpecifierTypeRepr`, since we forgot to add it to
that type's `classof` function.
resolves rdar://105480354
Weaken the precise tag check at loading swiftmodule to accept binary
modules build by a compiler with a tag where only the last digit is
different. We assume that the other digit in the version should ensure
compiler and stdlib compatibility. If the last digit doesn't match,
still raise a remark.
rdar://105158258
It appears that conditional casts require a check of the
type's metadata at runtime. There's no reason for us to
permit that at this time, since all such conditional
casts are going to fail, unless its the identity cast.
That is, a move-only type is currently only a subtype
of itself.
So for now, `is`, `as?`, `as!` casts from or to a
move-only type are now an error. The `as` casts
are permitted only if the two move-only types are
equal.
- Use the name lookup table instead of adding members from a macro expansion to the parent decl context.
- Require declaration macros to specify introduced names and used the declared names to guide macro expansions lazily.
Since values of generic type are currently assumed to always
support copying, we need to prevent move-only types from
being substituted for generic type parameters.
This approach leans on a `_Copyable` marker protocol to which
all generic type parameters implicitly must conform.
A few other changes in this initial implementation:
- Now every concrete type that can conform to Copyable will do so. This fixes issues with conforming to a protocol that requires Copyable.
- Narrowly ban writing a concrete type `[T]` when `T` is move-only.
Look through `try`/`await` markers when looking for
out of place if/switch expressions, and customize
the effect checking diagnostic such that we error
that `try`/`await` are redundant on `if`/`switch`
expressions.
Introduce SingleValueStmtExpr, which allows the
embedding of a statement in an expression context.
This then allows us to parse and type-check `if`
and `switch` statements as expressions, gated
behind the `IfSwitchExpression` experimental
feature for now. In the future,
SingleValueStmtExpr could also be used for e.g
`do` expressions.
For now, only single expression branches are
supported for producing a value from an
`if`/`switch` expression, and each branch is
type-checked independently. A multi-statement
branch may only appear if it ends with a `throw`,
and it may not `break`, `continue`, or `return`.
The placement of `if`/`switch` expressions is also
currently limited by a syntactic use diagnostic.
Currently they're only allowed in bindings,
assignments, throws, and returns. But this could
be lifted in the future if desired.
Diagnose situations where a sub-class or a protocol do not have all
of the reflection metadata attributes required by a superclass.
Resolves: rdar://103990788
This is just a way to opt-out a type from use of the attribute,
there is no code generation for such cases because the attribute
could never be reached.
Add support for freestanding declaration macros.
- Parse `@declaration` attribute.
- Type check and expand `MacroExpansionDecl`.
Known issues:
- Generic macros are not yet handled.
- Expansion does not work when the parent decl context is `BraceStmt`. Need to parse freestanding declaration macro expansions in `BraceStmt` as `MacroExpansionDecl`, and add expanded decls to name lookup.
