[ObjC] Implement @available in the Parser and AST
This patch adds a new AST node: ObjCAvailabilityCheckExpr, and teaches the
Parser and Sema to generate it. This node represents an availability check of
the form:
@available(macos 10.10, *);
Which will eventually compile to a runtime check of the host's OS version. This
is the first patch of the feature I proposed here:
http://lists.llvm.org/pipermail/cfe-dev/2016-July/049851.html
Differential Revision: https://reviews.llvm.org/D22171
llvm-svn: 275654
diff --git a/clang/lib/AST/Expr.cpp b/clang/lib/AST/Expr.cpp
index bd4cf39..091e878 100644
--- a/clang/lib/AST/Expr.cpp
+++ b/clang/lib/AST/Expr.cpp
@@ -2856,6 +2856,7 @@
case ObjCStringLiteralClass:
case ObjCEncodeExprClass:
case ObjCBoolLiteralExprClass:
+ case ObjCAvailabilityCheckExprClass:
case CXXUuidofExprClass:
case OpaqueValueExprClass:
// These never have a side-effect.