Suppress -Wunreachable-code-return warnings that can be fixed easily by rejiggering preprocessor conditions.

No behavior change.

Bug: chromium:1066980
Change-Id: I151bbd88ef39e18ae8f07c3e32e4b21de26520df
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2132780
Auto-Submit: Nico Weber <thakis@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Commit-Queue: Robert Sesek <rsesek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#755942}

base/allocator/allocator_extension.cc

@@ -24,15 +24,17 @@ void ReleaseFreeMemory() {
 bool GetNumericProperty(const char* name, size_t* value) {
 #if BUILDFLAG(USE_TCMALLOC)
   return ::MallocExtension::instance()->GetNumericProperty(name, value);
-#endif
+#else
   return false;
+#endif
 }
 
 bool SetNumericProperty(const char* name, size_t value) {
 #if BUILDFLAG(USE_TCMALLOC)
   return ::MallocExtension::instance()->SetNumericProperty(name, value);
-#endif
+#else
   return false;
+#endif
 }
 
 void GetHeapSample(std::string* writer) {
@@ -44,8 +46,9 @@ void GetHeapSample(std::string* writer) {
 bool IsHeapProfilerRunning() {
 #if BUILDFLAG(USE_TCMALLOC) && defined(ENABLE_PROFILING)
   return ::IsHeapProfilerRunning();
-#endif
+#else
   return false;
+#endif
 }
 
 void SetHooks(AllocHookFunc alloc_hook, FreeHookFunc free_hook) {
@@ -65,8 +68,9 @@ void SetHooks(AllocHookFunc alloc_hook, FreeHookFunc free_hook) {
 int GetCallStack(void** stack, int max_stack_size) {
 #if BUILDFLAG(USE_TCMALLOC)
   return MallocHook::GetCallerStackTrace(stack, max_stack_size, 0);
-#endif
+#else
   return 0;
+#endif
 }
 
 }  // namespace allocator

base/memory/madv_free_discardable_memory_posix.cc

@@ -60,9 +60,9 @@ base::MadvFreeSupport ProbePlatformMadvFreeSupport() {
   }
   PCHECK(!munmap(dummy_page, base::GetPageSize()));
   return support;
-#endif
+#else
-
   return base::MadvFreeSupport::kUnsupported;
+#endif
 }
 
 }  // namespace

base/trace_event/thread_instruction_count.cc

@@ -109,8 +109,9 @@ ThreadInstructionCount ThreadInstructionCount::Now() {
       << "Short reads of small size from kernel memory is not expected. If "
          "this fails, use HANDLE_EINTR.";
   return ThreadInstructionCount(instructions);
-#endif  // defined(OS_LINUX)
+#else
   return ThreadInstructionCount();
+#endif  // defined(OS_LINUX)
 }
 
 }  // namespace trace_event

chrome/browser/extensions/api/enterprise_reporting_private/device_info_fetcher_linux.cc

@@ -83,8 +83,9 @@ enterprise_reporting_private::SettingValue GetScreenlockSecured() {
   return lock_screen_enabled
              ? enterprise_reporting_private::SETTING_VALUE_ENABLED
              : enterprise_reporting_private::SETTING_VALUE_DISABLED;
-#endif  // defined(USE_GIO)
+#else
   return enterprise_reporting_private::SETTING_VALUE_UNKNOWN;
+#endif  // defined(USE_GIO)
 }
 
 // Implements the logic from the native host installation script. First find the

chrome/browser/search/search.cc

@@ -159,8 +159,9 @@ bool IsURLAllowedForSupervisedUser(const GURL& url, Profile* profile) {
 bool ShouldShowLocalNewTab(Profile* profile) {
 #if !defined(OS_ANDROID)
   return DefaultSearchProviderIsGoogle(profile);
-#endif
+#else
   return false;
+#endif
 }
 
 // Used to look up the URL to use for the New Tab page. Also tracks how we

chrome/browser/sharing/sharing_device_registration.cc

@@ -331,19 +331,18 @@ bool SharingDeviceRegistration::IsRemoteCopySupported() const {
 #if defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_LINUX) || \
     defined(OS_CHROMEOS)
   return base::FeatureList::IsEnabled(kRemoteCopyReceiver);
-#endif
+#else
-
   return false;
+#endif
 }
 
 bool SharingDeviceRegistration::IsPeerConnectionSupported() const {
 #if defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_LINUX) || \
     defined(OS_CHROMEOS)
   return base::FeatureList::IsEnabled(kSharingPeerConnectionReceiver);
-#endif  // defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_LINUX) ||
+#else
-        // defined(OS_CHROMEOS)
-
   return false;
+#endif
 }
 
 void SharingDeviceRegistration::SetEnabledFeaturesForTesting(

chrome/browser/sharing/sharing_service.cc

@@ -56,11 +56,11 @@ SharingMessageSender::DelegateType GetSendDelegateType(
   // logic once we wrap up the experiment and e.g. only send messages over a
   // certain size via WebRTC.
   return SharingMessageSender::DelegateType::kWebRtc;
-#endif  // defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_LINUX) ||
+#else
-        // defined(OS_CHROMEOS)
-
   // Only FCM is supported for non desktop OS.
   return SharingMessageSender::DelegateType::kFCM;
+#endif  // defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_LINUX) ||
+        // defined(OS_CHROMEOS)
 }
 
 }  // namespace

components/autofill/core/common/autofill_payments_features.cc

@@ -104,9 +104,10 @@ bool ShouldShowImprovedUserConsentForCreditCardSave() {
     (defined(OS_LINUX) && !defined(OS_CHROMEOS))
   // The new user consent UI is fully launched on MacOS, Windows and Linux.
   return true;
-#endif
+#else
   // Chrome OS does not have the new UI.
   return false;
+#endif
 }
 
 }  // namespace features

content/browser/renderer_host/render_widget_host_view_aura.cc

@@ -2189,8 +2189,9 @@ bool RenderWidgetHostViewAura::NeedsInputGrab() {
 bool RenderWidgetHostViewAura::NeedsMouseCapture() {
 #if defined(OS_LINUX) && !defined(OS_CHROMEOS)
   return NeedsInputGrab();
-#endif
+#else
   return false;
+#endif
 }
 
 void RenderWidgetHostViewAura::SetTooltipsEnabled(bool enable) {

gpu/config/gpu_test_config.cc

@@ -43,6 +43,7 @@ GPUTestConfig::OS GetCurrentOS() {
     return GPUTestConfig::kOsWin8;
   if (major_version == 10)
     return GPUTestConfig::kOsWin10;
+  return GPUTestConfig::kOsUnknown;
 #elif defined(OS_MACOSX)
   int32_t major_version = 0;
   int32_t minor_version = 0;
@@ -75,12 +76,14 @@ GPUTestConfig::OS GetCurrentOS() {
         return GPUTestConfig::kOsMacCatalina;
     }
   }
+  return GPUTestConfig::kOsUnknown;
 #elif defined(OS_ANDROID)
   return GPUTestConfig::kOsAndroid;
 #elif defined(OS_FUCHSIA)
   return GPUTestConfig::kOsFuchsia;
+#else
+#error "unknown os"
 #endif
-  return GPUTestConfig::kOsUnknown;
 }
 
 }  // namespace anonymous

media/base/supported_types.cc

@@ -267,13 +267,15 @@ bool IsDefaultSupportedVideoType(const VideoType& type) {
       // If the AV1 decoder is enabled, or if we're on Q or later, yes.
 #if BUILDFLAG(ENABLE_AV1_DECODER)
       return IsColorSpaceSupported(type.color_space);
-#elif defined(OS_ANDROID)
+#else
+#if defined(OS_ANDROID)
       if (base::android::BuildInfo::GetInstance()->is_at_least_q() &&
           IsColorSpaceSupported(type.color_space)) {
         return true;
       }
 #endif
       return false;
+#endif
 
     case kCodecVP9:
       // Color management required for HDR to not look terrible.

net/socket/tcp_socket_posix.cc

@@ -654,8 +654,9 @@ bool TCPSocketPosix::GetEstimatedRoundTripTime(base::TimeDelta* out_rtt) const {
     return false;
   *out_rtt = rtt;
   return true;
-#endif  // defined(TCP_INFO)
+#else
   return false;
+#endif  // defined(TCP_INFO)
 }
 
 }  // namespace net

services/service_manager/sandbox/linux/sandbox_seccomp_bpf_linux.cc

@@ -132,16 +132,18 @@ bool SandboxSeccompBPF::IsSeccompBPFDesired() {
       *base::CommandLine::ForCurrentProcess();
   return !command_line.HasSwitch(switches::kNoSandbox) &&
          !command_line.HasSwitch(switches::kDisableSeccompFilterSandbox);
-#endif  // USE_SECCOMP_BPF
+#else
   return false;
+#endif  // USE_SECCOMP_BPF
 }
 
 bool SandboxSeccompBPF::SupportsSandbox() {
 #if BUILDFLAG(USE_SECCOMP_BPF)
   return SandboxBPF::SupportsSeccompSandbox(
       SandboxBPF::SeccompLevel::SINGLE_THREADED);
-#endif
+#else
   return false;
+#endif
 }
 
 #if !defined(OS_NACL_NONSFI)
@@ -150,8 +152,9 @@ bool SandboxSeccompBPF::SupportsSandboxWithTsync() {
 #if BUILDFLAG(USE_SECCOMP_BPF)
   return SandboxBPF::SupportsSeccompSandbox(
       SandboxBPF::SeccompLevel::MULTI_THREADED);
-#endif
+#else
   return false;
+#endif
 }
 
 std::unique_ptr<BPFBasePolicy> SandboxSeccompBPF::PolicyForSandboxType(

third_party/blink/renderer/core/css/resolver/style_resolver.cc

@@ -138,8 +138,9 @@ bool ShouldComputeBaseComputedStyle(const ComputedStyle* base_computed_style) {
   // the fact that we have a base computed style when DCHECKs are enabled, and
   // call ValidateBaseComputedStyle() to check that the optimization was sound.
   return true;
-#endif  // !DCHECK_IS_ON()
+#else
   return !base_computed_style;
+#endif  // !DCHECK_IS_ON()
 }
 
 // Compare the base computed style with the one we compute to validate that the

third_party/blink/renderer/core/input/keyboard_event_manager.cc

@@ -591,8 +591,8 @@ bool KeyboardEventManager::CurrentCapsLockState() {
 }
 
 WebInputEvent::Modifiers KeyboardEventManager::GetCurrentModifierState() {
-  unsigned modifiers = 0;
 #if defined(OS_MACOSX)
+  unsigned modifiers = 0;
   UInt32 current_modifiers = GetCurrentKeyModifiers();
   if (current_modifiers & ::shiftKey)
     modifiers |= WebInputEvent::kShiftKey;
@@ -602,11 +602,11 @@ WebInputEvent::Modifiers KeyboardEventManager::GetCurrentModifierState() {
     modifiers |= WebInputEvent::kAltKey;
   if (current_modifiers & ::cmdKey)
     modifiers |= WebInputEvent::kMetaKey;
+  return static_cast<WebInputEvent::Modifiers>(modifiers);
 #else
   // TODO(crbug.com/538289): Implement on other platforms.
   return static_cast<WebInputEvent::Modifiers>(0);
 #endif
-  return static_cast<WebInputEvent::Modifiers>(modifiers);
 }
 
 }  // namespace blink

third_party/blink/renderer/core/scroll/scrollbar_theme_aura.cc

@@ -139,9 +139,9 @@ bool ScrollbarThemeAura::SupportsDragSnapBack() const {
 // is true for at least GTK and QT apps).
 #if (defined(OS_LINUX) && !defined(OS_CHROMEOS))
   return false;
-#endif
+#else
-
   return true;
+#endif
 }
 
 int ScrollbarThemeAura::ScrollbarThickness(ScrollbarControlSize control_size) {

ui/views/window/dialog_delegate.cc

@@ -62,12 +62,14 @@ bool DialogDelegate::CanSupportCustomFrame(gfx::NativeView parent) {
 #if defined(OS_LINUX) && BUILDFLAG(ENABLE_DESKTOP_AURA)
   // The new style doesn't support unparented dialogs on Linux desktop.
   return parent != nullptr;
-#elif defined(OS_WIN)
+#else
+#if defined(OS_WIN)
   // The new style doesn't support unparented dialogs on Windows Classic themes.
   if (!ui::win::IsAeroGlassEnabled())
     return parent != nullptr;
 #endif
   return true;
+#endif
 }
 
 // static