Add separate check scheme

The address sanitizer prints spurious warnings; create a separate
"check" scheme that enables the sanitizers and use "displaymode" for
releases.

displaymode.xcodeproj/xcshareddata/xcschemes/check.xcscheme

@@ -0,0 +1,99 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "1420"
+   version = "1.3">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "2885595C2296CD410095626C"
+               BuildableName = "displaymode"
+               BlueprintName = "displaymode"
+               ReferencedContainer = "container:displaymode.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES">
+      <Testables>
+      </Testables>
+   </TestAction>
+   <LaunchAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      enableAddressSanitizer = "YES"
+      enableUBSanitizer = "YES"
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
+      allowLocationSimulation = "YES"
+      viewDebuggingEnabled = "No">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "2885595C2296CD410095626C"
+            BuildableName = "displaymode"
+            BlueprintName = "displaymode"
+            ReferencedContainer = "container:displaymode.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+      <CommandLineArguments>
+         <CommandLineArgument
+            argument = "d"
+            isEnabled = "YES">
+         </CommandLineArgument>
+      </CommandLineArguments>
+      <AdditionalOptions>
+         <AdditionalOption
+            key = "NSZombieEnabled"
+            value = "YES"
+            isEnabled = "YES">
+         </AdditionalOption>
+         <AdditionalOption
+            key = "MallocScribble"
+            value = ""
+            isEnabled = "YES">
+         </AdditionalOption>
+      </AdditionalOptions>
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Release"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "2885595C2296CD410095626C"
+            BuildableName = "displaymode"
+            BlueprintName = "displaymode"
+            ReferencedContainer = "container:displaymode.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>

displaymode.xcodeproj/xcshareddata/xcschemes/displaymode.xcscheme

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
    LastUpgradeVersion = "1320"
-   version = "1.3">
+   version = "1.8">
    <BuildAction
       parallelizeBuildables = "YES"
       buildImplicitDependencies = "YES">
@@ -43,15 +43,15 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      enableAddressSanitizer = "YES"
       enableASanStackUseAfterReturn = "YES"
-      enableUBSanitizer = "YES"
+      disableMainThreadChecker = "YES"
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
       ignoresPersistentStateOnLaunch = "NO"
       debugDocumentVersioning = "YES"
       migratedStopOnEveryIssue = "YES"
       debugServiceExtension = "internal"
+      enableGPUValidationMode = "1"
       allowLocationSimulation = "YES">
       <BuildableProductRunnable
          runnableDebuggingMode = "0">