diff --git a/media/sctp/sctptransport.cc b/media/sctp/sctptransport.cc
index 6e047e2a87..b3459858d7 100644
--- a/media/sctp/sctptransport.cc
+++ b/media/sctp/sctptransport.cc
@@ -36,6 +36,7 @@ enum PreservedErrno {
 #include "rtc_base/helpers.h"
 #include "rtc_base/logging.h"
 #include "rtc_base/numerics/safe_conversions.h"
+#include "rtc_base/stringutils.h"
 #include "rtc_base/thread_checker.h"
 #include "rtc_base/trace_event.h"
 #include "usrsctplib/usrsctp.h"
@@ -312,8 +313,8 @@ class SctpTransport::UsrSctpWrapper {
     SctpTransport* transport = static_cast<SctpTransport*>(addr);
     RTC_LOG(LS_VERBOSE) << "global OnSctpOutboundPacket():"
                         << "addr: " << addr << "; length: " << length
-                        << "; tos: " << std::hex << static_cast<int>(tos)
-                        << "; set_df: " << std::hex << static_cast<int>(set_df);
+                        << "; tos: " << rtc::ToHex(tos)
+                        << "; set_df: " << rtc::ToHex(set_df);
 
     VerboseLogPacket(data, length, SCTP_DUMP_OUTBOUND);
     // Note: We have to copy the data; the caller will delete it.
@@ -1056,7 +1057,7 @@ void SctpTransport::OnStreamResetEvent(
   const int num_sids = (evt->strreset_length - sizeof(*evt)) /
                        sizeof(evt->strreset_stream_list[0]);
   RTC_LOG(LS_VERBOSE) << "SCTP_STREAM_RESET_EVENT(" << debug_name_
-                      << "): Flags = 0x" << std::hex << evt->strreset_flags
+                      << "): Flags = 0x" << rtc::ToHex(evt->strreset_flags)
                       << " (" << ListFlags(evt->strreset_flags) << ")";
   RTC_LOG(LS_VERBOSE) << "Assoc = " << evt->strreset_assoc_id << ", Streams = ["
                       << ListArray(evt->strreset_stream_list, num_sids)
diff --git a/modules/audio_device/win/audio_device_core_win.cc b/modules/audio_device/win/audio_device_core_win.cc
index 9476f311b1..731d4614e8 100644
--- a/modules/audio_device/win/audio_device_core_win.cc
+++ b/modules/audio_device/win/audio_device_core_win.cc
@@ -40,6 +40,7 @@
 
 #include "rtc_base/logging.h"
 #include "rtc_base/platform_thread.h"
+#include "rtc_base/stringutils.h"
 #include "rtc_base/thread_annotations.h"
 #include "system_wrappers/include/sleep.h"
 
@@ -1872,8 +1873,8 @@ int32_t AudioDeviceWindowsCore::InitPlayout() {
   if (SUCCEEDED(hr)) {
     RTC_LOG(LS_VERBOSE) << "Audio Engine's current rendering mix format:";
     // format type
-    RTC_LOG(LS_VERBOSE) << "wFormatTag     : 0x" << std::hex
-                        << pWfxOut->wFormatTag << std::dec << " ("
+    RTC_LOG(LS_VERBOSE) << "wFormatTag     : 0x"
+                        << rtc::ToHex(pWfxOut->wFormatTag) << " ("
                         << pWfxOut->wFormatTag << ")";
     // number of channels (i.e. mono, stereo...)
     RTC_LOG(LS_VERBOSE) << "nChannels      : " << pWfxOut->nChannels;
@@ -1947,8 +1948,8 @@ int32_t AudioDeviceWindowsCore::InitPlayout() {
     _playChannels = Wfx.nChannels;
 
     RTC_LOG(LS_VERBOSE) << "VoE selected this rendering format:";
-    RTC_LOG(LS_VERBOSE) << "wFormatTag         : 0x" << std::hex
-                        << Wfx.wFormatTag << std::dec << " (" << Wfx.wFormatTag
+    RTC_LOG(LS_VERBOSE) << "wFormatTag         : 0x"
+                        << rtc::ToHex(Wfx.wFormatTag) << " (" << Wfx.wFormatTag
                         << ")";
     RTC_LOG(LS_VERBOSE) << "nChannels          : " << Wfx.nChannels;
     RTC_LOG(LS_VERBOSE) << "nSamplesPerSec     : " << Wfx.nSamplesPerSec;
@@ -2189,8 +2190,8 @@ int32_t AudioDeviceWindowsCore::InitRecording() {
   if (SUCCEEDED(hr)) {
     RTC_LOG(LS_VERBOSE) << "Audio Engine's current capturing mix format:";
     // format type
-    RTC_LOG(LS_VERBOSE) << "wFormatTag     : 0x" << std::hex
-                        << pWfxIn->wFormatTag << std::dec << " ("
+    RTC_LOG(LS_VERBOSE) << "wFormatTag     : 0x"
+                        << rtc::ToHex(pWfxIn->wFormatTag) << " ("
                         << pWfxIn->wFormatTag << ")";
     // number of channels (i.e. mono, stereo...)
     RTC_LOG(LS_VERBOSE) << "nChannels      : " << pWfxIn->nChannels;
@@ -2262,8 +2263,8 @@ int32_t AudioDeviceWindowsCore::InitRecording() {
     _recChannels = Wfx.Format.nChannels;
 
     RTC_LOG(LS_VERBOSE) << "VoE selected this capturing format:";
-    RTC_LOG(LS_VERBOSE) << "wFormatTag        : 0x" << std::hex
-                        << Wfx.Format.wFormatTag << std::dec << " ("
+    RTC_LOG(LS_VERBOSE) << "wFormatTag        : 0x"
+                        << rtc::ToHex(Wfx.Format.wFormatTag) << " ("
                         << Wfx.Format.wFormatTag << ")";
     RTC_LOG(LS_VERBOSE) << "nChannels         : " << Wfx.Format.nChannels;
     RTC_LOG(LS_VERBOSE) << "nSamplesPerSec    : " << Wfx.Format.nSamplesPerSec;
@@ -3327,8 +3328,8 @@ DWORD AudioDeviceWindowsCore::DoCaptureThread() {
         // IAudioClient::Stop, IAudioClient::Reset, and releasing the audio
         // client.
         RTC_LOG(LS_ERROR) << "IAudioCaptureClient::GetBuffer returned"
-                          << " AUDCLNT_E_BUFFER_ERROR, hr = 0x" << std::hex
-                          << hr << std::dec;
+                          << " AUDCLNT_E_BUFFER_ERROR, hr = 0x"
+                          << rtc::ToHex(hr);
         goto Exit;
       }
 
@@ -3841,7 +3842,7 @@ int32_t AudioDeviceWindowsCore::_GetDeviceName(IMMDevice* pDevice,
     hr = pDevice->OpenPropertyStore(STGM_READ, &pProps);
     if (FAILED(hr)) {
       RTC_LOG(LS_ERROR) << "IMMDevice::OpenPropertyStore failed, hr = 0x"
-                        << std::hex << hr << std::dec;
+                        << rtc::ToHex(hr);
     }
   }
 
@@ -3853,21 +3854,21 @@ int32_t AudioDeviceWindowsCore::_GetDeviceName(IMMDevice* pDevice,
     hr = pProps->GetValue(PKEY_Device_FriendlyName, &varName);
     if (FAILED(hr)) {
       RTC_LOG(LS_ERROR) << "IPropertyStore::GetValue failed, hr = 0x"
-                        << std::hex << hr << std::dec;
+                        << rtc::ToHex(hr);
     }
   }
 
   if ((SUCCEEDED(hr)) && (VT_EMPTY == varName.vt)) {
     hr = E_FAIL;
     RTC_LOG(LS_ERROR) << "IPropertyStore::GetValue returned no value,"
-                      << " hr = 0x" << std::hex << hr << std::dec;
+                      << " hr = 0x" << rtc::ToHex(hr);
   }
 
   if ((SUCCEEDED(hr)) && (VT_LPWSTR != varName.vt)) {
     // The returned value is not a wide null terminated string.
     hr = E_UNEXPECTED;
     RTC_LOG(LS_ERROR) << "IPropertyStore::GetValue returned unexpected"
-                      << " type, hr = 0x" << std::hex << hr << std::dec;
+                      << " type, hr = 0x" << rtc::ToHex(hr);
   }
 
   if (SUCCEEDED(hr) && (varName.pwszVal != NULL)) {
@@ -4056,16 +4057,16 @@ int32_t AudioDeviceWindowsCore::_EnumerateEndpointDevicesAll(
     hr = pEndpoint->GetState(&dwState);
     CONTINUE_ON_ERROR(hr);
     if (dwState & DEVICE_STATE_ACTIVE)
-      RTC_LOG(LS_VERBOSE) << "state (0x" << std::hex << dwState << std::dec
+      RTC_LOG(LS_VERBOSE) << "state (0x" << rtc::ToHex(dwState)
                           << ")  : *ACTIVE*";
     if (dwState & DEVICE_STATE_DISABLED)
-      RTC_LOG(LS_VERBOSE) << "state (0x" << std::hex << dwState << std::dec
+      RTC_LOG(LS_VERBOSE) << "state (0x" << rtc::ToHex(dwState)
                           << ")  : DISABLED";
     if (dwState & DEVICE_STATE_NOTPRESENT)
-      RTC_LOG(LS_VERBOSE) << "state (0x" << std::hex << dwState << std::dec
+      RTC_LOG(LS_VERBOSE) << "state (0x" << rtc::ToHex(dwState)
                           << ")  : NOTPRESENT";
     if (dwState & DEVICE_STATE_UNPLUGGED)
-      RTC_LOG(LS_VERBOSE) << "state (0x" << std::hex << dwState << std::dec
+      RTC_LOG(LS_VERBOSE) << "state (0x" << rtc::ToHex(dwState)
                           << ")  : UNPLUGGED";
 
     // Check the hardware volume capabilities.
@@ -4077,16 +4078,16 @@ int32_t AudioDeviceWindowsCore::_EnumerateEndpointDevicesAll(
     CONTINUE_ON_ERROR(hr);
     if (dwHwSupportMask & ENDPOINT_HARDWARE_SUPPORT_VOLUME)
       // The audio endpoint device supports a hardware volume control
-      RTC_LOG(LS_VERBOSE) << "hwmask (0x" << std::hex << dwHwSupportMask
-                          << std::dec << ") : HARDWARE_SUPPORT_VOLUME";
+      RTC_LOG(LS_VERBOSE) << "hwmask (0x" << rtc::ToHex(dwHwSupportMask)
+                          << ") : HARDWARE_SUPPORT_VOLUME";
     if (dwHwSupportMask & ENDPOINT_HARDWARE_SUPPORT_MUTE)
       // The audio endpoint device supports a hardware mute control
-      RTC_LOG(LS_VERBOSE) << "hwmask (0x" << std::hex << dwHwSupportMask
-                          << std::dec << ") : HARDWARE_SUPPORT_MUTE";
+      RTC_LOG(LS_VERBOSE) << "hwmask (0x" << rtc::ToHex(dwHwSupportMask)
+                          << ") : HARDWARE_SUPPORT_MUTE";
     if (dwHwSupportMask & ENDPOINT_HARDWARE_SUPPORT_METER)
       // The audio endpoint device supports a hardware peak meter
-      RTC_LOG(LS_VERBOSE) << "hwmask (0x" << std::hex << dwHwSupportMask
-                          << std::dec << ") : HARDWARE_SUPPORT_METER";
+      RTC_LOG(LS_VERBOSE) << "hwmask (0x" << rtc::ToHex(dwHwSupportMask)
+                          << ") : HARDWARE_SUPPORT_METER";
 
     // Check the channel count (#channels in the audio stream that enters or
     // leaves the audio endpoint device)
diff --git a/modules/pacing/paced_sender.cc b/modules/pacing/paced_sender.cc
index a5546fe633..f8383187a9 100644
--- a/modules/pacing/paced_sender.cc
+++ b/modules/pacing/paced_sender.cc
@@ -353,7 +353,7 @@ void PacedSender::Process() {
 }
 
 void PacedSender::ProcessThreadAttached(ProcessThread* process_thread) {
-  RTC_LOG(LS_INFO) << "ProcessThreadAttached 0x" << std::hex << process_thread;
+  RTC_LOG(LS_INFO) << "ProcessThreadAttached 0x" << process_thread;
   rtc::CritScope cs(&process_thread_lock_);
   process_thread_ = process_thread;
 }
diff --git a/modules/video_capture/windows/device_info_ds.cc b/modules/video_capture/windows/device_info_ds.cc
index 5e158fe478..7cba0d40d4 100644
--- a/modules/video_capture/windows/device_info_ds.cc
+++ b/modules/video_capture/windows/device_info_ds.cc
@@ -10,11 +10,10 @@
 
 #include "modules/video_capture/windows/device_info_ds.h"
 
-#include <ios>  // std::hex
-
 #include "modules/video_capture/video_capture_config.h"
 #include "modules/video_capture/windows/help_functions_ds.h"
 #include "rtc_base/logging.h"
+#include "rtc_base/stringutils.h"
 
 #include <dvdmedia.h>
 #include <streams.h>
@@ -75,7 +74,7 @@ DeviceInfoDS::DeviceInfoDS()
       //
       RTC_LOG(LS_INFO) << __FUNCTION__
                        << ": CoInitializeEx(NULL, COINIT_APARTMENTTHREADED)"
-                       << " => RPC_E_CHANGED_MODE, error 0x" << std::hex << hr;
+                       << " => RPC_E_CHANGED_MODE, error 0x" << rtc::ToHex(hr);
     }
   }
 }
@@ -93,7 +92,7 @@ int32_t DeviceInfoDS::Init() {
                                 IID_ICreateDevEnum, (void**)&_dsDevEnum);
   if (hr != NOERROR) {
     RTC_LOG(LS_INFO) << "Failed to create CLSID_SystemDeviceEnum, error 0x"
-                     << std::hex << hr;
+                     << rtc::ToHex(hr);
     return -1;
   }
   return 0;
@@ -132,7 +131,7 @@ int32_t DeviceInfoDS::GetDeviceInfo(uint32_t deviceNumber,
                                                  &_dsMonikerDevEnum, 0);
   if (hr != NOERROR) {
     RTC_LOG(LS_INFO) << "Failed to enumerate CLSID_SystemDeviceEnum, error 0x"
-                     << std::hex << hr << ". No webcam exist?";
+                     << rtc::ToHex(hr) << ". No webcam exist?";
     return 0;
   }
 
@@ -223,7 +222,7 @@ IBaseFilter* DeviceInfoDS::GetDeviceFilter(const char* deviceUniqueIdUTF8,
                                                  &_dsMonikerDevEnum, 0);
   if (hr != NOERROR) {
     RTC_LOG(LS_INFO) << "Failed to enumerate CLSID_SystemDeviceEnum, error 0x"
-                     << std::hex << hr << ". No webcam exist?";
+                     << rtc::ToHex(hr) << ". No webcam exist?";
     return 0;
   }
   _dsMonikerDevEnum->Reset();
diff --git a/modules/video_capture/windows/sink_filter_ds.cc b/modules/video_capture/windows/sink_filter_ds.cc
index 76d2fa9119..c2db44b3f2 100644
--- a/modules/video_capture/windows/sink_filter_ds.cc
+++ b/modules/video_capture/windows/sink_filter_ds.cc
@@ -10,12 +10,11 @@
 
 #include "modules/video_capture/windows/sink_filter_ds.h"
 
-#include <ios>  // std::hex
-
 #include "modules/video_capture/windows/help_functions_ds.h"
 #include "rtc_base/checks.h"
 #include "rtc_base/logging.h"
 #include "rtc_base/platform_thread.h"
+#include "rtc_base/stringutils.h"
 
 #include <dvdmedia.h>  // VIDEOINFOHEADER2
 #include <initguid.h>
@@ -148,7 +147,7 @@ CaptureInputPin::GetMediaType(IN int iPosition, OUT CMediaType* pmt) {
   RTC_LOG(LS_INFO) << "GetMediaType position " << iPosition << ", width "
                    << _requestedCapability.width << ", height "
                    << _requestedCapability.height << ", biCompression 0x"
-                   << std::hex << pvi->bmiHeader.biCompression;
+                   << rtc::ToHex(pvi->bmiHeader.biCompression);
   return NOERROR;
 }
 
@@ -188,8 +187,8 @@ CaptureInputPin::CheckMediaType(IN const CMediaType* pMediaType) {
 
     RTC_LOG(LS_INFO) << "CheckMediaType width:" << pvi->bmiHeader.biWidth
                      << " height:" << pvi->bmiHeader.biHeight
-                     << " Compression:0x" << std::hex
-                     << pvi->bmiHeader.biCompression;
+                     << " Compression:0x"
+                     << rtc::ToHex(pvi->bmiHeader.biCompression);
 
     if (*SubType == MEDIASUBTYPE_MJPG &&
         pvi->bmiHeader.biCompression == MAKEFOURCC('M', 'J', 'P', 'G')) {
@@ -233,8 +232,8 @@ CaptureInputPin::CheckMediaType(IN const CMediaType* pMediaType) {
 
     RTC_LOG(LS_INFO) << "CheckMediaType width:" << pvi->bmiHeader.biWidth
                      << " height:" << pvi->bmiHeader.biHeight
-                     << " Compression:0x" << std::hex
-                     << pvi->bmiHeader.biCompression;
+                     << " Compression:0x"
+                     << rtc::ToHex(pvi->bmiHeader.biCompression);
 
     _resultingCapability.width = pvi->bmiHeader.biWidth;
 
diff --git a/p2p/base/p2ptransportchannel.cc b/p2p/base/p2ptransportchannel.cc
index c769097f98..486e293c26 100644
--- a/p2p/base/p2ptransportchannel.cc
+++ b/p2p/base/p2ptransportchannel.cc
@@ -2119,9 +2119,8 @@ void P2PTransportChannel::OnConnectionDestroyed(Connection* connection) {
   unpinged_connections_.erase(*iter);
   connections_.erase(iter);
 
-  RTC_LOG(LS_INFO) << ToString() << ": Removed connection "
-                   << std::hex << connection << std::dec << " ("
-                   << connections_.size() << " remaining)";
+  RTC_LOG(LS_INFO) << ToString() << ": Removed connection " << connection
+                   << " (" << connections_.size() << " remaining)";
 
   // If this is currently the selected connection, then we need to pick a new
   // one. The call to SortConnectionsAndUpdateState will pick a new one. It
diff --git a/rtc_base/unittest_main.cc b/rtc_base/unittest_main.cc
index aa8a11bb5a..e32ca77185 100644
--- a/rtc_base/unittest_main.cc
+++ b/rtc_base/unittest_main.cc
@@ -45,11 +45,10 @@ void TestInvalidParameterHandler(const wchar_t* expression,
                                  const wchar_t* file,
                                  unsigned int line,
                                  uintptr_t pReserved) {
+  // In order to log `expression`, `function`, and `file` here, we would have
+  // to convert them to const char*. std::wcsrtombs can do that, but it's
+  // locale dependent.
   RTC_LOG(LS_ERROR) << "InvalidParameter Handler called.  Exiting.";
-  RTC_LOG(LS_ERROR) << expression << std::endl
-                    << function << std::endl
-                    << file << std::endl
-                    << line;
   exit(1);
 }
 void TestPureCallHandler() {