diff --git a/absl/base/attributes.h b/absl/base/attributes.h
index 5ea5ee3e..f4949898 100644
--- a/absl/base/attributes.h
+++ b/absl/base/attributes.h
@@ -559,7 +559,7 @@
 #undef ABSL_ATTRIBUTE_UNUSED
 #define ABSL_ATTRIBUTE_UNUSED __attribute__((__unused__))
 #else
-#define ABSL_ATTRIBUTE_UNUSED
+#define ABSL_ATTRIBUTE_UNUSED [[maybe_unused]]
 #endif
 
 // ABSL_ATTRIBUTE_INITIAL_EXEC
diff --git a/absl/container/internal/raw_hash_set.h b/absl/container/internal/raw_hash_set.h
index d4fe8f5c..27418d13 100644
--- a/absl/container/internal/raw_hash_set.h
+++ b/absl/container/internal/raw_hash_set.h
@@ -1924,7 +1924,7 @@ HashtablezInfoHandle SampleHashtablezInfo(size_t sizeof_slot, size_t sizeof_key,
   // In SOO, we sample on the first insertion so if this is an empty SOO case
   // (e.g. when reserve is called), then we still need to sample.
   if (kSooEnabled && was_soo && c.size() == 0) {
-    return Sample(sizeof_slot, sizeof_key, sizeof_value, SooCapacity());
+    return Sample(sizeof_slot, sizeof_key, sizeof_value, (int16_t)SooCapacity());
   }
   // For non-SOO cases, we sample whenever the capacity is increasing from zero
   // to non-zero.
@@ -3525,7 +3525,7 @@ class raw_hash_set {
     assert(is_soo());
     if (!ShouldSampleHashtablezInfo<CharAlloc>()) return HashtablezInfoHandle{};
     return Sample(sizeof(slot_type), sizeof(key_type), sizeof(value_type),
-                  SooCapacity());
+                  (int16_t)SooCapacity());
   }
 
   inline void destroy_slots() {
diff --git a/absl/copts/GENERATED_AbseilCopts.cmake b/absl/copts/GENERATED_AbseilCopts.cmake
index da2282fe..4c7fc26f 100644
--- a/absl/copts/GENERATED_AbseilCopts.cmake
+++ b/absl/copts/GENERATED_AbseilCopts.cmake
@@ -181,8 +181,6 @@ list(APPEND ABSL_MSVC_FLAGS
     "/wd4005"
     "/wd4068"
     "/wd4180"
-    "/wd4244"
-    "/wd4267"
     "/wd4503"
     "/wd4800"
     "/DNOMINMAX"
diff --git a/absl/copts/GENERATED_copts.bzl b/absl/copts/GENERATED_copts.bzl
index b9e0071e..dd8410ec 100644
--- a/absl/copts/GENERATED_copts.bzl
+++ b/absl/copts/GENERATED_copts.bzl
@@ -182,8 +182,6 @@ ABSL_MSVC_FLAGS = [
     "/wd4005",
     "/wd4068",
     "/wd4180",
-    "/wd4244",
-    "/wd4267",
     "/wd4503",
     "/wd4800",
     "/DNOMINMAX",
diff --git a/absl/copts/copts.py b/absl/copts/copts.py
index 2d85ac74..4875d668 100644
--- a/absl/copts/copts.py
+++ b/absl/copts/copts.py
@@ -118,10 +118,6 @@ MSVC_WARNING_FLAGS = [
     "/wd4068",  # unknown pragma
     # qualifier applied to function type has no meaning; ignored
     "/wd4180",
-    # conversion from 'type1' to 'type2', possible loss of data
-    "/wd4244",
-    # conversion from 'size_t' to 'type', possible loss of data
-    "/wd4267",
     # The decorated name was longer than the compiler limit
     "/wd4503",
     # forcing value to bool 'true' or 'false' (performance warning)
diff --git a/absl/debugging/symbolize.cc b/absl/debugging/symbolize.cc
index 638d3954..6b817075 100644
--- a/absl/debugging/symbolize.cc
+++ b/absl/debugging/symbolize.cc
@@ -14,7 +14,7 @@
 
 #include "absl/debugging/symbolize.h"
 
-#ifdef _WIN32
+#if defined(_WIN32) && !defined(NDEBUG)
 #include <winapifamily.h>
 #if !(WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP)) || \
     WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
diff --git a/absl/debugging/symbolize_win32.inc b/absl/debugging/symbolize_win32.inc
index 53a099a1..34d210d6 100644
--- a/absl/debugging/symbolize_win32.inc
+++ b/absl/debugging/symbolize_win32.inc
@@ -35,15 +35,15 @@ ABSL_NAMESPACE_BEGIN
 
 static HANDLE process = NULL;
 
-void InitializeSymbolizer(const char*) {
-  if (process != nullptr) {
-    return;
-  }
+namespace {
+void InitializeSymbolizerImpl() {
+
   process = GetCurrentProcess();
 
   // Symbols are not loaded until a reference is made requiring the
   // symbols be loaded. This is the fastest, most efficient way to use
   // the symbol handler.
+
   SymSetOptions(SYMOPT_DEFERRED_LOADS | SYMOPT_UNDNAME);
   if (!SymInitialize(process, nullptr, true)) {
     // GetLastError() returns a Win32 DWORD, but we assign to
@@ -54,6 +54,36 @@ void InitializeSymbolizer(const char*) {
   }
 }
 
+bool LookupAndInitialize(const void* pc, SYMBOL_INFO* symbol) {
+  auto hProcess = (process != NULL) ? process : GetCurrentProcess();
+  if (SymFromAddr(hProcess, reinterpret_cast<DWORD64>(pc), nullptr, symbol) != TRUE) {
+    if (GetLastError() == ERROR_INVALID_HANDLE && process == NULL) {
+      InitializeSymbolizerImpl();
+      if (SymFromAddr(process, reinterpret_cast<DWORD64>(pc), nullptr, symbol) != TRUE) {
+        return false;
+      }
+    } else {
+      return false;
+    }
+    return false;
+  }
+  return true;
+}
+}
+
+void InitializeSymbolizer(const char*) {
+  if (process != nullptr) {
+    return;
+  }
+
+  alignas(SYMBOL_INFO) char buf[sizeof(SYMBOL_INFO) + MAX_SYM_NAME];
+  SYMBOL_INFO* symbol = reinterpret_cast<SYMBOL_INFO*>(buf);
+  symbol->SizeOfStruct = sizeof(SYMBOL_INFO);
+  symbol->MaxNameLen = MAX_SYM_NAME;
+
+  static_cast<void>(LookupAndInitialize(reinterpret_cast<const void*>(&InitializeSymbolizer), symbol));
+}
+
 bool Symbolize(const void* pc, char* out, int out_size) {
   if (out_size <= 0) {
     return false;
@@ -62,9 +92,11 @@ bool Symbolize(const void* pc, char* out, int out_size) {
   SYMBOL_INFO* symbol = reinterpret_cast<SYMBOL_INFO*>(buf);
   symbol->SizeOfStruct = sizeof(SYMBOL_INFO);
   symbol->MaxNameLen = MAX_SYM_NAME;
-  if (!SymFromAddr(process, reinterpret_cast<DWORD64>(pc), nullptr, symbol)) {
+
+  if(!LookupAndInitialize(pc, symbol)) {
     return false;
   }
+
   const size_t out_size_t = static_cast<size_t>(out_size);
   strncpy(out, symbol->Name, out_size_t);
   if (out[out_size_t - 1] != '\0') {