Swift: Default to Swift 3.0 with Xcode 8.3 and later

Xcode 8.3 has dropped support for Swift 2.3 so that compiler and
feature detection failed.

Closes #16742

2 files changed, 14 insertions, 1 deletions

diff --git a/Tests/SwiftMix/ObjCMain.m b/Tests/SwiftMix/ObjCMain.m
index 7fa90aefbe..5a8700cfcc 100644
--- a/Tests/SwiftMix/ObjCMain.m
+++ b/Tests/SwiftMix/ObjCMain.m
@@ -1,4 +1,10 @@
 #import "SwiftMix-Swift.h"
 int ObjCMain(int argc, char const* const argv[]) {
-  return [SwiftMainClass SwiftMain:argc argv:argv];
+  if ([SwiftMainClass respondsToSelector:@selector(SwiftMain:argv:)]) {
+    return [SwiftMainClass SwiftMain:argc argv:argv];
+  }
+  if ([SwiftMainClass respondsToSelector:@selector(SwiftMainWithArgc:argv:)]) {
+    return [SwiftMainClass SwiftMainWithArgc:argc argv:argv];
+  }
+  return -1;
 }
diff --git a/Tests/SwiftMix/SwiftMain.swift b/Tests/SwiftMix/SwiftMain.swift
index 3629ac82a6..921439a613 100644
--- a/Tests/SwiftMix/SwiftMain.swift
+++ b/Tests/SwiftMix/SwiftMain.swift
@@ -3,10 +3,17 @@ import Foundation
 @objc class SwiftMainClass : NSObject {
   class func SwiftMain(argc:Int, argv:UnsafePointer<UnsafePointer<CChar>>) -> Int32 {
     dump("argc: \(argc)")
+#if swift(>=3.0)
+    for i in 0 ..< argc {
+      let argi = String(cString:argv[i]);
+      dump("arg[\(i)]: \(argi)");
+    }
+#else
     for (var i = 0; i < argc; ++i) {
       let argi = String.fromCString(argv[i])
       dump("arg[\(i)]: \(argi)");
     }
+#endif
     return 0;
   }
 }