Drop the Xcode 9.4 dependency.

Make.config

@@ -47,10 +47,6 @@ XCODE_VERSION=11.0
 XCODE_URL=http://xamarin-storage/bot-provisioning/xcodes/Xcode_11_GM_Seed_2.xip
 XCODE_DEVELOPER_ROOT=/Applications/Xcode11-GM2.app/Contents/Developer
 
-XCODE94_VERSION=9.4
-XCODE94_URL=http://xamarin-storage/bot-provisioning/xcodes/Xcode_9.4.xip
-XCODE94_DEVELOPER_ROOT=/Applications/Xcode94.app/Contents/Developer
-
 # Mono version embedded in XI/XM (NEEDED_MONO_VERSION/BRANCH) are specified in mk/mono.mk
 include $(TOP)/mk/mono.mk
 MONO_HASH := $(NEEDED_MONO_VERSION)
@@ -136,15 +132,11 @@ APPLETLS_DEFINES = -d:XAMARIN_APPLETLS
 endif
 
 XCODE_MAC_SDKROOT=$(XCODE_DEVELOPER_ROOT)/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk
-XCODE94_MAC_SDKROOT=$(XCODE94_DEVELOPER_ROOT)/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk
 
 # The MAC_* variables do not contain the -mmacosx-version-min flag on purpose: each usage must specify it separately.
 MAC_CC=$(CCACHE)$(XCODE_DEVELOPER_ROOT)/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang -isysroot $(XCODE_MAC_SDKROOT) -stdlib=libc++
 MAC_CXX=$(CCACHE)$(XCODE_DEVELOPER_ROOT)/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ -isysroot $(XCODE_MAC_SDKROOT) -stdlib=libc++
 
-MAC32_CC=$(CCACHE)$(XCODE94_DEVELOPER_ROOT)/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang -isysroot $(XCODE94_MAC_SDKROOT) -stdlib=libc++
-MAC32_CXX=$(CCACHE)$(XCODE94_DEVELOPER_ROOT)/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ -isysroot $(XCODE94_MAC_SDKROOT) -stdlib=libc++
-
 MAC_INSTALL_VERSION ?= git
 IOS_INSTALL_VERSION ?= git
 

builds/Makefile

@@ -76,7 +76,7 @@ else
 # Configuration for the mono sdk makefiles
 #
 SDK_ARGS= \
-	XCODE_DIR=$(XCODE_DEVELOPER_ROOT) XCODE32_DIR=$(XCODE94_DEVELOPER_ROOT) \
+	XCODE_DIR=$(XCODE_DEVELOPER_ROOT) \
 	IOS_VERSION=$(IOS_SDK_VERSION) IOS_VERSION_MIN=$(MIN_IOS_SDK_VERSION) \
 	TVOS_VERSION=$(TVOS_SDK_VERSION) TVOS_VERSION_MIN=$(MIN_TVOS_SDK_VERSION) \
 	WATCHOS_VERSION=$(WATCH_SDK_VERSION) WATCHOS_VERSION_MIN=$(MIN_WATCHOS_SDK_VERSION) \

mk/mono.mk

@@ -1,4 +1,4 @@
-NEEDED_MONO_VERSION := 29b1ac19c961b959a09097dbc0fe4cd567cc5298
+NEEDED_MONO_VERSION := 70d690305348cb30cf620db0679ba1173dc7adb0
 NEEDED_MONO_BRANCH := 2019-08
 
 MONO_DIRECTORY := mono

runtime/Makefile

@@ -418,8 +418,6 @@ MAC_ARCHITECTURES = x86_64
 
 CLANG_ARCH = $(addprefix -arch ,$(MAC_ARCHITECTURES))
 MAC_CLANG = DEVELOPER_DIR=$(XCODE_DEVELOPER_ROOT) $(MAC_CC) -mmacosx-version-min=$(MIN_OSX_SDK_VERSION)
-MAC32_CLANG = DEVELOPER_DIR=$(XCODE94_DEVELOPER_ROOT) $(MAC32_CC) -mmacosx-version-min=$(MIN_OSX_SDK_VERSION)
-MAC64_CLANG = DEVELOPER_DIR=$(XCODE_DEVELOPER_ROOT) $(MAC_CC) -mmacosx-version-min=$(MIN_OSX_SDK_VERSION)
 
 MAC_SHIPPED_HEADERS = xamarin/launch.h
 
@@ -469,25 +467,25 @@ STATIC_LAUNCHER$(2)_OBJECTS = $$(foreach src,$$(MAC_SOURCES),.libs/mac/$$(basena
 SYSTEM_LAUNCHER$(2)_OBJECTS = $$(foreach src,$$(MAC_SOURCES),.libs/mac/$$(basename $$(src))$(3).system.$(1).o)
 
 .libs/mac/%$(3).dylib.$(1).o: %.m $$(SHARED_HEADERS) | .libs/mac
-	$$(call Q_2,OBJC,  [mac]) $(MAC$(5)_CLANG) -arch $(1) $(4) -c $$(MAC_OBJC_CFLAGS) $$(MAC_CFLAGS) -DDYNAMIC_MONO_RUNTIME -DDYLIB -o $$@ $$<
+	$$(call Q_2,OBJC,  [mac]) $(MAC_CLANG) -arch $(1) $(4) -c $$(MAC_OBJC_CFLAGS) $$(MAC_CFLAGS) -DDYNAMIC_MONO_RUNTIME -DDYLIB -o $$@ $$<
 
 .libs/mac/%$(3).dylib.$(1).o: %.s $$(SHARED_HEADERS) | .libs/mac
-	$$(call Q_2,ASM,   [mac]) $(MAC$(5)_CLANG) -arch $(1) $(4) -c $$(MAC_CFLAGS) -DDYNAMIC_MONO_RUNTIME -DDYLIB -o $$@ $$<
+	$$(call Q_2,ASM,   [mac]) $(MAC_CLANG) -arch $(1) $(4) -c $$(MAC_CFLAGS) -DDYNAMIC_MONO_RUNTIME -DDYLIB -o $$@ $$<
 
 .libs/mac/%$(3).static.$(1).o: %.s $$(SHARED_HEADERS) | .libs/mac
-	$$(call Q_2,ASM,   [mac]) $(MAC$(5)_CLANG) -arch $(1) $(4) -c $$(MAC_STATIC_CFLAGS) -o $$@ $$<
+	$$(call Q_2,ASM,   [mac]) $(MAC_CLANG) -arch $(1) $(4) -c $$(MAC_STATIC_CFLAGS) -o $$@ $$<
 
 .libs/mac/%$(3).static.$(1).o: %.m $$(SHARED_HEADERS) | .libs/mac
-	$$(call Q_2,OBJC,  [mac]) $(MAC$(5)_CLANG) -arch $(1) $(4) $$(MAC_OBJC_CFLAGS) -c $$(MAC_STATIC_CFLAGS) -o $$@ $$<
+	$$(call Q_2,OBJC,  [mac]) $(MAC_CLANG) -arch $(1) $(4) $$(MAC_OBJC_CFLAGS) -c $$(MAC_STATIC_CFLAGS) -o $$@ $$<
 
 .libs/mac/%$(3).system.$(1).o: %.m $$(SHARED_HEADERS) | .libs/mac
-	$$(call Q_2,OBJC,  [mac]) $(MAC$(5)_CLANG) -arch $(1) $(4) $$(MAC_OBJC_CFLAGS) -c $$(MAC_CFLAGS) -DDYNAMIC_MONO_RUNTIME -o $$@ $$<
+	$$(call Q_2,OBJC,  [mac]) $(MAC_CLANG) -arch $(1) $(4) $$(MAC_OBJC_CFLAGS) -c $$(MAC_CFLAGS) -DDYNAMIC_MONO_RUNTIME -o $$@ $$<
 
 .libs/mac/%$(3).system.$(1).o: %.s $$(SHARED_HEADERS) | .libs/mac
-	$$(call Q_2,ASM,   [mac]) $(MAC$(5)_CLANG) -arch $(1) $(4) -c $(MAC_CFLAGS) -DDYNAMIC_MONO_RUNTIME -o $$@ $$<
+	$$(call Q_2,ASM,   [mac]) $(MAC_CLANG) -arch $(1) $(4) -c $(MAC_CFLAGS) -DDYNAMIC_MONO_RUNTIME -o $$@ $$<
 
 .libs/mac/libxammac$(3).$(1).dylib: $$(DYNAMIC_DYLIB$(2)_OBJECTS)
-	$$(call Q_2,LD,    [mac]) $(MAC$(5)_CLANG) -arch $(1) -dynamiclib $$(MAC_LDFLAGS) -Wl,-install_name,libxammac$(3).dylib -o $$@ $$^ $$(addprefix -Xlinker -U -Xlinker ,$$(ALLOWED_UNDEFINED_SYMBOLS))
+	$$(call Q_2,LD,    [mac]) $(MAC_CLANG) -arch $(1) -dynamiclib $$(MAC_LDFLAGS) -Wl,-install_name,libxammac$(3).dylib -o $$@ $$^ $$(addprefix -Xlinker -U -Xlinker ,$$(ALLOWED_UNDEFINED_SYMBOLS))
 
 .libs/mac/libxammac$(3).$(1).a: $$(STATIC_LAUNCHER$(2)_OBJECTS)
 	$$(call Q_2,LIB,   [mac]) xcrun libtool -no_warning_for_no_symbols -static -o $$@ $$^

system-dependencies.sh

@@ -548,11 +548,6 @@ function check_xcode () {
 	# must have latest Xcode in /Applications/Xcode<version>.app
 	check_specific_xcode
 	install_coresimulator
-	# Xcode 9,4 does not longer start on catalina
-	local current_os=$(sw_vers -productVersion)
-	if test $current_os != "10.15"; then
-		check_specific_xcode "94"
-	fi
 
 	local XCODE_DEVELOPER_ROOT=`grep ^XCODE_DEVELOPER_ROOT= Make.config | sed 's/.*=//'`
 	local IOS_SDK_VERSION=`grep ^IOS_SDK_VERSION= Make.config | sed 's/.*=//'`

tests/common/Configuration.cs

@@ -315,7 +315,7 @@ public static string SourceRoot {
 				// might need tweaking.
 				if (mt_src_root == null)
 #if MONOMAC
-					mt_src_root = Path.GetFullPath (Path.Combine (TestAssemblyDirectory, "../../.."));
+					mt_src_root = RootPath;
 #else
 					mt_src_root = Path.GetFullPath (Path.Combine (TestAssemblyDirectory, "../../../.."));
 #endif

tests/common/ProductTests.cs

@@ -70,7 +70,7 @@ public void MinOSVersion (Profile profile, MachO.LoadCommands load_command, Mach
 			foreach (var machoFile in machoFiles) {
 				var fatfile = MachO.Read (machoFile);
 				foreach (var slice in fatfile) {
-					if (slice.IsDynamicLibrary && slice.Architecture == MachO.Architectures.x86_64 && slice.Parent.size < 10240 /* this is the dummy x86_64 slice to appease Apple's notarization tooling */)
+					if (slice.IsDynamicLibrary && slice.Architecture == MachO.Architectures.x86_64 && slice.Parent != null && slice.Parent.size < 10240 /* this is the dummy x86_64 slice to appease Apple's notarization tooling */)
 						continue;
 					var any_load_command = false;
 					foreach (var lc in slice.load_commands) {

tests/mmptest/mmptest.csproj

@@ -113,6 +113,9 @@
       <Link>SdkVersions.cs</Link>
     </Compile>
     <Compile Include="src\TargetFrameworkMutateTests.cs" />
+    <Compile Include="..\..\tools\common\MachO.cs">
+      <Link>MachO.cs</Link>
+    </Compile>
   </ItemGroup>
   <ItemGroup>
     <None Include="Info.plist" />

tests/mmptest/src/CodeStrippingTests.cs

@@ -4,6 +4,7 @@
 using NUnit.Framework;
 
 using Xamarin.Utils;
+using Xamarin.Tests;
 
 namespace Xamarin.MMP.Tests
 {
@@ -59,6 +60,10 @@ void StripTestCore (TI.UnifiedTestConfig test, bool debugStrips, bool releaseStr
 		[TestCase (false, false, false)]
 		public void ShouldStripMonoPosixHelper (bool? strip, bool debugStrips, bool releaseStrips)
 		{
+			var posixHelper = Path.Combine (Configuration.SdkRootXM, "lib", "libMonoPosixHelper.dylib");
+			if (Xamarin.MachO.GetArchitectures (posixHelper).Count < 2)
+				Assert.Ignore ($"libMonoPosixHelper.dylib is not a fat library.");
+
 			MMPTests.RunMMPTest (tmpDir =>
 			{
 				TI.UnifiedTestConfig test = CreateStripTestConfig (strip, tmpDir);
@@ -90,16 +95,21 @@ public void ExplictStripOption_ThirdPartyLibrary_AndWarnsIfSo (bool? strip, bool
 		{
 			MMPTests.RunMMPTest (tmpDir =>
 			{
-				string originalLocation = Path.Combine (TI.FindRootDirectory (), MonoPosixOffset);
+				string originalLocation = Path.Combine (Configuration.SourceRoot, "tests", "test-libraries", "libtest-fat.macos.dylib");
 				string newLibraryLocation =  Path.Combine (tmpDir, "libTest.dylib");
 				File.Copy (originalLocation, newLibraryLocation);
 
 				TI.UnifiedTestConfig test = CreateStripTestConfig (strip, tmpDir, $" --native-reference=\"{newLibraryLocation}\"");
 				test.Release = true;
 
-				string buildOutput = TI.TestUnifiedExecutable (test).BuildOutput;
+				var testOutput = TI.TestUnifiedExecutable (test);
+				string buildOutput = testOutput.BuildOutput;
 				Assert.AreEqual (shouldStrip, DidAnyLipoStrip (buildOutput), "lipo usage did not match expectations");
-				Assert.AreEqual (shouldStrip, buildOutput.Contains ("MM2108"), "Warning did not match expectations");
+				if (shouldStrip) {
+					testOutput.Messages.AssertWarning (2108, "libTest.dylib was stripped of architectures except x86_64 to comply with App Store restrictions. This could break existing codesigning signatures. Consider stripping the library with lipo or disabling with --optimize=-trim-architectures");
+				} else {
+					testOutput.Messages.AssertWarningCount (0);
+				}
 			});
 		}
 

tools/common/MachO.cs

@@ -232,10 +232,19 @@ public static IEnumerable<MachOFile> Read (string filename)
 				}
 			} else {
 				var mf = file as MachOFile;
-				if (mf != null)
+				if (mf != null) {
 					yield return mf;
-				else
-					throw ErrorHelper.CreateError (1604, "File of type {0} is not a MachO file ({1}).", file.GetType ().Name, filename);
+					yield break;
+				}
+
+				var sl = file as StaticLibrary;
+				if (sl != null) {
+					foreach (var obj in sl.ObjectFiles)
+						yield return obj;
+					yield break;
+				}
+
+				throw ErrorHelper.CreateError (1604, "File of type {0} is not a MachO file ({1}).", file.GetType ().Name, filename);
 			}
 		}