diff --git a/Shims/Shimulator/TestCrashShim/TestCrashShim.m b/Shims/Shimulator/TestCrashShim/TestCrashShim.m
index ac1c19307..d26a30942 100644
--- a/Shims/Shimulator/TestCrashShim/TestCrashShim.m
+++ b/Shims/Shimulator/TestCrashShim/TestCrashShim.m
@@ -42,7 +42,7 @@ static void PrintProcessInfo(void)
   FBDebugLog(@"Environment %@", processInfo.environment);
 }
 
-__attribute__((constructor)) static void EntryPoint()
+__attribute__((constructor)) static void EntryPoint(void)
 {
   NSLog(@"Start of Shimulator");
 
diff --git a/Shims/Shimulator/TestLoadingShim/FBXCTestMain.m b/Shims/Shimulator/TestLoadingShim/FBXCTestMain.m
index d510acee6..d5002fcf3 100644
--- a/Shims/Shimulator/TestLoadingShim/FBXCTestMain.m
+++ b/Shims/Shimulator/TestLoadingShim/FBXCTestMain.m
@@ -25,7 +25,7 @@
  #import <AppKit/AppKit.h>
 #endif
 
-__attribute__((constructor)) static void XCTestMainEntryPoint()
+__attribute__((constructor)) static void XCTestMainEntryPoint(void)
 {
   FBDebugLog(@"[XCTestMainEntryPoint] Running inside: %@", [[NSBundle mainBundle] bundleIdentifier]);
   if (!NSProcessInfo.processInfo.environment[kEnv_ShimStartXCTest]) {
@@ -44,7 +44,7 @@
   FBDebugLog(@"[XCTestMainEntryPoint] End of XCTestMainEntryPoint");
 }
 
-BOOL FBLoadXCTestIfNeeded()
+BOOL FBLoadXCTestIfNeeded(void)
 {
   FBDebugLog(@"Env: %@", [NSProcessInfo processInfo].environment);
 
@@ -83,7 +83,7 @@ BOOL FBLoadXCTestIfNeeded()
   return NO;
 }
 
-void FBDeployBlockWhenAppLoads(void (^mainBlock)())
+void FBDeployBlockWhenAppLoads(void (^mainBlock)(void))
 {
 #if TARGET_OS_IPHONE
   NSString *notification = UIApplicationDidFinishLaunchingNotification;
@@ -113,7 +113,7 @@ static id XCTestCase__xctTestIdentifier(id self, SEL sel)
   return [[XCTTestIdentifier_class alloc] initWithStringRepresentation:[NSString stringWithFormat:@"%@/%@", classNameOut, methodNameOut] preserveModulePrefix:YES];
 }
 
-BOOL FBXCTestMain()
+BOOL FBXCTestMain(void)
 {
   if (!FBLoadXCTestIfNeeded()) {
     exit(TestShimExitCodeXCTestFailedLoading);
diff --git a/Shims/Shimulator/TestReporterShim/XCTestReporterShim.m b/Shims/Shimulator/TestReporterShim/XCTestReporterShim.m
index 85ddba7a1..9a68eb180 100644
--- a/Shims/Shimulator/TestReporterShim/XCTestReporterShim.m
+++ b/Shims/Shimulator/TestReporterShim/XCTestReporterShim.m
@@ -21,7 +21,6 @@
 
 static NSString *const XCTestFilterArg = @"XCTest";
 static NSString *const XCTestFrameworkName = @"XCTest";
-static NSString *const XCTestProbeClassName = @"XCTestProbe";
 static NSString *const XCTestSuiteClassName = @"XCTestSuite";
 
 static FILE *__stdout;
@@ -63,16 +62,6 @@
   return tests;
 }
 
-// Key used by objc_setAssociatedObject
-static int TestDescriptionKey;
-
-static NSString *TestCase_nameOrDescription(id self, SEL cmd)
-{
-  id description = objc_getAssociatedObject(self, &TestDescriptionKey);
-  NSCAssert(description != nil, @"Value for `TestNameKey` wasn't set.");
-  return description;
-}
-
 static char *const kEventQueueLabel = "xctool.events";
 
 @interface XCToolAssertionHandler : NSAssertionHandler
@@ -97,7 +86,7 @@ - (void)handleFailureInFunction:(NSString *)functionName
 
 @end
 
-static dispatch_queue_t EventQueue()
+static dispatch_queue_t EventQueue(void)
 {
   static dispatch_queue_t eventQueue = {0};
   static dispatch_once_t onceToken;
@@ -364,7 +353,7 @@ static void XCPerformTestWithSuppressedExpectedAssertionFailures(id self, SEL or
   [currentThreadDict removeObjectForKey:NSAssertionHandlerKey];
 }
 
-static void XCWaitForDebuggerIfNeeded()
+static void XCWaitForDebuggerIfNeeded(void)
 {
   static dispatch_once_t onceToken;
   dispatch_once(&onceToken, ^{
@@ -441,7 +430,7 @@ static BOOL XCTestCase__enableSymbolication(id self, SEL sel)
  *  to the pipe reader. Printing "\n" should be safe because reader is skipping
  *  empty lines.
  */
-static void PrintNewlineAndCloseFDs()
+static void PrintNewlineAndCloseFDs(void)
 {
   if (__stdout == NULL) {
     return;
@@ -453,7 +442,7 @@ static void PrintNewlineAndCloseFDs()
 
 #pragma mark - Entry
 
-static void SwizzleXCTestMethodsIfAvailable()
+static void SwizzleXCTestMethodsIfAvailable(void)
 {
   if ([[[NSBundle mainBundle] bundleIdentifier] hasPrefix:@"com.apple.dt.xctest"]) {
     // Start from Xcode 11.1, XCTest will try to connect to testmanagerd service
@@ -698,7 +687,7 @@ static id SimServiceContext_deviceSetWithPath_error(id cls, SEL sel, NSString *p
   return msgsend(cls, originalSelector, simDeviceSetPath, error);
 }
 
-static void SwizzleXcodebuildMethods()
+static void SwizzleXcodebuildMethods(void)
 {
   static dispatch_once_t token;
   dispatch_once(&token, ^{
@@ -719,7 +708,7 @@ static void SwizzleXcodebuildMethods()
   });
 }
 
-__attribute__((constructor)) static void EntryPoint()
+__attribute__((constructor)) static void EntryPoint(void)
 {
   // Unset so we don't cascade into any other process that might be spawned.
   unsetenv("DYLD_INSERT_LIBRARIES");
@@ -765,7 +754,7 @@ static void SwizzleXcodebuildMethods()
   }
 }
 
-__attribute__((destructor)) static void ExitPoint()
+__attribute__((destructor)) static void ExitPoint(void)
 {
   PrintNewlineAndCloseFDs();
 }