[Driver] Link arclite on iOS 8 and OS X 10.10. (#3123)

(macOS? OS X? How does this work for past OSs?)

Noticed by inspection. Xcode doesn't use swiftc to link, and the few
things that went into arclite between iOS 7 and iOS 8 weren't critical,
but we should still get this right.

Author: jrose-apple

lib/Driver/ToolChains.cpp

@@ -996,11 +996,9 @@ toolchains::Darwin::constructInvocation(const LinkJobAction &job,
   // we wouldn't have to replicate Clang's logic here.
   bool wantsObjCRuntime = false;
   if (Triple.isiOS())
-    wantsObjCRuntime = Triple.isOSVersionLT(8);
-  else if (Triple.isWatchOS())
-    wantsObjCRuntime = Triple.isOSVersionLT(2);
+    wantsObjCRuntime = Triple.isOSVersionLT(9);
   else if (Triple.isMacOSX())
-    wantsObjCRuntime = Triple.isMacOSXVersionLT(10, 10);
+    wantsObjCRuntime = Triple.isMacOSXVersionLT(10, 11);
 
   if (context.Args.hasFlag(options::OPT_link_objc_runtime,
                            options::OPT_no_link_objc_runtime,

test/Driver/linker.swift

@@ -35,8 +35,18 @@
 // RUN: FileCheck -check-prefix COMPLEX %s < %t.complex.txt
 
 // RUN: %swiftc_driver -driver-print-jobs -target x86_64-apple-macosx10.9 -g %s | FileCheck -check-prefix DEBUG %s
-// RUN: %swiftc_driver -driver-print-jobs -target x86_64-apple-macosx10.10   %s | FileCheck -check-prefix NO_ARCLITE %s
-// RUN: %swiftc_driver -driver-print-jobs -target x86_64-apple-ios8.0        %s | FileCheck -check-prefix NO_ARCLITE %s
+
+// RUN: %swiftc_driver -driver-print-jobs -target x86_64-apple-macosx10.10   %s > %t.simple-macosx10.10.txt
+// RUN: FileCheck %s < %t.simple-macosx10.10.txt
+// RUN: FileCheck -check-prefix SIMPLE %s < %t.simple-macosx10.10.txt
+
+// RUN: %swiftc_driver -driver-print-jobs -target x86_64-apple-ios8.0        %s > %t.simple-ios8.txt
+// RUN: FileCheck -check-prefix IOS_ARCLITE %s < %t.simple-ios8.txt
+
+// RUN: %swiftc_driver -driver-print-jobs -target x86_64-apple-macosx10.11   %s | FileCheck -check-prefix NO_ARCLITE %s
+// RUN: %swiftc_driver -driver-print-jobs -target x86_64-apple-ios9.0        %s | FileCheck -check-prefix NO_ARCLITE %s
+// RUN: %swiftc_driver -driver-print-jobs -target arm64-apple-tvos9.0        %s | FileCheck -check-prefix NO_ARCLITE %s
+// RUN: %swiftc_driver -driver-print-jobs -target armv7k-apple-watchos2.0    %s | FileCheck -check-prefix NO_ARCLITE %s
 
 // RUN: rm -rf %t && mkdir %t
 // RUN: touch %t/a.o
@@ -225,6 +235,12 @@
 // DEBUG: linker
 // DEBUG: -o linker.dSYM
 
+
+
+// IOS_ARCLITE: bin/ld{{"? }}
+// IOS_ARCLITE: -force_load {{[^ ]+/lib/arc/libarclite_iphonesimulator.a}}
+// IOS_ARCLITE: -o {{[^ ]+}}
+
 // NO_ARCLITE: bin/ld{{"? }}
 // NO_ARCLITE-NOT: arclite
 // NO_ARCLITE: -o {{[^ ]+}}