Remove the diagnostic that warns when an availability check is unnecessary
because the minimum deployment target ensures it will always be true. This
diagnostic is valuable (it tells users that they have dead fallback code) but
can also be super annoying when a source file is shared between projects with
different deployment targets. There is not currently a good mechanism to
suppress these warnings (for example, by expressing a "compatibility version" in
the source or as a build setting) and so it is better to turn the diagnostic
off.
rdar://problem/22337402
Previously we treated the * platform as checking for the minimum
deployment target, but that's definitely unnecessary.
There is a bit of a hack here to avoid diagnosing the 'else' branch as
unreachable: if a constant true/false came from #available, ignore it.
'Ss' appears in manglings tens of thousands of times in the standard library and is also incredibly frequent in other modules. This alone is enough to shrink the standard library by 59KB.
Swift SVN r32409
instead of being an expression.
To the user, this has a couple of behavior changes, stemming from its non-expression-likeness.
- #available cannot be parenthesized anymore
- #available is in its own clause, not used in a 'where' clause of if/let.
Also, the implementation in the compiler is simpler and fits the model better. This
fixes:
<rdar://problem/20904820> Following a "let" condition with #available is incorrectly rejected
Swift SVN r28521
Change the syntax of availability queries from #available(iOS >= 8.0, OSX >= 10.10, *) to
This change reflects the fact that now that we spell the query '#available()' rather than
'#os()', the specification is about availability of the APIs introduced in a particular OS
release rather than an explicit range of OS versions on which the developer expects the
code to run.
There is a Fix-It to remove '>=' to ease adopting the new syntax.
Swift SVN r28025
Enable checking for uses of potentially unavailable APIs. There is
a frontend option to disable it: -disable-availability-checking.
This commit updates the SDK overlays with @availability() annotations for the
declarations where the overlay refers to potentially unavailable APIs. It also changes
several tests that refer to potentially unavailable APIs to use either #available()
or @availability annotations.
Swift SVN r27272
The API review list found it confusing that if #os() and #if os() looked so similar, so
change the availability checking query to be spelled #available:
if #available(iOS >= 9.0, *) {
...
}
Swift SVN r26995
On platforms that are not explicitly mentioned in the #os() guard, this new '*'
availability check generates a version comparison against the minimum deployment target.
This construct, based on feedback from API review, is designed to ease porting
to new platforms. Because new platforms typically branch from
existing platforms, the wildcard allows an API availability check to do the "right"
thing (executing the guarded branch accessing newer APIs) on the new platform without
requiring a modification to every availability guard in the program.
So, if the programmer writes:
if #os(OSX >= 10.10, *) {
. . .
}
and then ports the code to iOS, the body will execute.
We still do compile-time availability checking with '*', so the compiler will
emit errors for references to potentially unavailable symbols in the body when compiled
for iOS.
We require a '*' clause on all #os() guards to force developers to
"future proof" their availability checks against the introduction of new a platform.
Swift SVN r26988
We no longer need or use it since we can always refer to the same bit on
the applied function when deciding whether to inline during mandatory
inlining.
Resolves rdar://problem/19478366.
Swift SVN r26534
Most tests were using %swift or similar substitutions, which did not
include the target triple and SDK. The driver was defaulting to the
host OS. Thus, we could not run the tests when the standard library was
not built for OS X.
Swift SVN r24504
This patch adds SILGen for the API availability (#os(...)) construct. To do so,
it (1) adds version range information to the AvailabilityQueryExpr AST in Sema,
during type refinement context construction; and (2) uses that version range,
during SILGen, to emit a call to the standard library's
_stdlib_isOSVersionAtLeast function.
Swift SVN r22348
