diff --git a/sycl/doc/developer/ContributeToDPCPP.md b/sycl/doc/developer/ContributeToDPCPP.md
index 63b7d4f4632a3..f7471a97b5205 100644
--- a/sycl/doc/developer/ContributeToDPCPP.md
+++ b/sycl/doc/developer/ContributeToDPCPP.md
@@ -40,10 +40,10 @@ to signify the component changed, e.g.: `[PI]`, `[CUDA]`, `[Doc]`.
 According to 
 [LLVM Coding Standards](https://llvm.org/docs/CodingStandards.html#include-iostream-is-forbidden),
 the use `#include <iostream>` is forbidden in library files. Instead, the
-sycl/detail/iostream_proxy.hpp header offers the functionality of <iostream>
+detail/iostream_proxy.hpp header offers the functionality of <iostream>
 without its static constructor.
-This header should be used in place of <iostream> in DPC++ headers and runtime
-library files.
+This header should be used in place of <iostream> in DPC++ runtime
+library files. In DPC++ header files only <iosfwd> should be used.
 
 ## Tests development
 
diff --git a/sycl/include/sycl/backend_types.hpp b/sycl/include/sycl/backend_types.hpp
index d1b89832064ce..a6cdb3bf0aad7 100644
--- a/sycl/include/sycl/backend_types.hpp
+++ b/sycl/include/sycl/backend_types.hpp
@@ -10,7 +10,8 @@
 
 #include <sycl/detail/defines_elementary.hpp> // for __SYCL2020_DEPRECATED
 
-#include <ostream> // for operator<<, ostream
+#include <iosfwd> // for operator<<, ostream
+#include <sycl/detail/export.hpp>
 
 namespace sycl {
 inline namespace _V1 {
@@ -36,34 +37,7 @@ template <backend Backend, typename SYCLObjectT>
 using backend_return_t =
     typename backend_traits<Backend>::template return_type<SYCLObjectT>;
 
-inline std::ostream &operator<<(std::ostream &Out, backend be) {
-  switch (be) {
-  case backend::host:
-    Out << "host";
-    break;
-  case backend::opencl:
-    Out << "opencl";
-    break;
-  case backend::ext_oneapi_level_zero:
-    Out << "ext_oneapi_level_zero";
-    break;
-  case backend::ext_oneapi_cuda:
-    Out << "ext_oneapi_cuda";
-    break;
-  case backend::ext_intel_esimd_emulator:
-    Out << "ext_intel_esimd_emulator";
-    break;
-  case backend::ext_oneapi_hip:
-    Out << "ext_oneapi_hip";
-    break;
-  case backend::ext_native_cpu:
-    Out << "ext_native_cpu";
-    break;
-  case backend::all:
-    Out << "all";
-  }
-  return Out;
-}
+__SYCL_EXPORT std::ostream &operator<<(std::ostream &Out, backend be);
 
 } // namespace _V1
 } // namespace sycl
diff --git a/sycl/include/sycl/bit_cast.hpp b/sycl/include/sycl/bit_cast.hpp
index e9f92b7cf6c50..23dfef3ee82f3 100644
--- a/sycl/include/sycl/bit_cast.hpp
+++ b/sycl/include/sycl/bit_cast.hpp
@@ -14,9 +14,11 @@
 #include <version> // defines __cpp_lib_bit_cast
 #endif
 
+#include <sycl/detail/defines_elementary.hpp> // __has_builtin
+
 #if __cpp_lib_bit_cast
 #include <bit>
-#elif !defined(__has_builtin) || !__has_builtin(__builtin_bit_cast)
+#elif !__has_builtin(__builtin_bit_cast)
 #include <sycl/detail/memcpy.hpp>
 #endif
 
@@ -24,8 +26,7 @@ namespace sycl {
 inline namespace _V1 {
 
 template <typename To, typename From>
-#if __cpp_lib_bit_cast ||                                                      \
-    (defined(__has_builtin) && __has_builtin(__builtin_bit_cast))
+#if __cpp_lib_bit_cast || __has_builtin(__builtin_bit_cast)
 constexpr
 #endif
     std::enable_if_t<sizeof(To) == sizeof(From) &&
@@ -37,7 +38,7 @@ constexpr
   return std::bit_cast<To>(from);
 #else // __cpp_lib_bit_cast
 
-#if defined(__has_builtin) && __has_builtin(__builtin_bit_cast)
+#if __has_builtin(__builtin_bit_cast)
   return __builtin_bit_cast(To, from);
 #else // __has_builtin(__builtin_bit_cast)
   static_assert(std::is_trivially_default_constructible<To>::value,
diff --git a/sycl/include/sycl/detail/accessor_iterator.hpp b/sycl/include/sycl/detail/accessor_iterator.hpp
index 97c5385bf3624..5c993811dca23 100644
--- a/sycl/include/sycl/detail/accessor_iterator.hpp
+++ b/sycl/include/sycl/detail/accessor_iterator.hpp
@@ -13,8 +13,8 @@
 #include <sycl/id.hpp>            // for id
 
 #include <cstddef>  // for size_t
+#include <iosfwd>   // for operator<<, ostream, ptrdiff_t
 #include <iterator> // for random_access_iterator_tag
-#include <ostream>  // for operator<<, ostream, ptrdiff_t
 
 /// \file accessor_iterator.hpp
 /// The file contains implementation of accessor iterator class.
@@ -45,6 +45,10 @@ class accessor;
 
 namespace detail {
 
+struct accessor_iterator_data;
+__SYCL_EXPORT std::ostream &operator<<(std::ostream &os,
+                                       const accessor_iterator_data &it);
+
 template <typename DataT, int Dimensions> class accessor_iterator {
 public:
   using difference_type = std::ptrdiff_t;
@@ -331,22 +335,30 @@ template <typename DataT, int Dimensions> class accessor_iterator {
 #ifndef NDEBUG
   // Could be useful for debugging, but not a part of the official API,
   // therefore only available in builds with assertions enabled.
+  friend struct accessor_iterator_data;
   friend std::ostream &operator<<(std::ostream &os,
                                   const accessor_iterator &it) {
-    os << "accessor_iterator {\n";
-    os << "\tMLinearId: " << it.MLinearId << "\n";
-    os << "\tMEnd: " << it.MEnd << "\n";
-    os << "\tMStaticOffset: " << it.MStaticOffset << "\n";
-    os << "\tMPerRowOffset: " << it.MPerRowOffset << "\n";
-    os << "\tMPerSliceOffset: " << it.MPerSliceOffset << "\n";
-    os << "\tMRowSize: " << it.MRowSize << "\n";
-    os << "\tMSliceSize: " << it.MSliceSize << "\n";
-    os << "\tMAccessorIsRanged: " << it.MAccessorIsRanged << "\n";
-    os << "}";
-    return os;
+    return os << accessor_iterator_data(it);
   }
 #endif // NDEBUG
 };
+// non-templated copy of accessor_iterator to pass to library
+struct accessor_iterator_data {
+  template <typename DataT, int Dimensions>
+  accessor_iterator_data(accessor_iterator<DataT, Dimensions> it)
+      : MLinearId(it.MLinearId), MEnd(it.MEnd), MStaticOffset(it.MStaticOffset),
+        MPerSliceOffset(it.MPerSliceOffset), MPerRowOffset(it.MPerRowOffset),
+        MRowSize(it.MRowSize), MSliceSize(it.MSliceSize),
+        MAccessorIsRanged(it.MAccessorIsRanged) {}
+  size_t MLinearId;
+  size_t MEnd;
+  size_t MStaticOffset;
+  size_t MPerSliceOffset;
+  size_t MPerRowOffset;
+  size_t MRowSize;
+  size_t MSliceSize;
+  bool MAccessorIsRanged;
+};
 } // namespace detail
 } // namespace _V1
 } // namespace sycl
diff --git a/sycl/include/sycl/detail/common.hpp b/sycl/include/sycl/detail/common.hpp
index a8c94e32d81c6..5867d199deb0d 100644
--- a/sycl/include/sycl/detail/common.hpp
+++ b/sycl/include/sycl/detail/common.hpp
@@ -173,14 +173,14 @@ inline std::string codeToString(pi_int32 code) {
                           "Native API returns: "
 
 #ifndef __SYCL_SUPPRESS_PI_ERROR_REPORT
-#include <sycl/detail/iostream_proxy.hpp>
 // TODO: rename all names with direct use of OCL/OPENCL to be backend agnostic.
 #define __SYCL_REPORT_PI_ERR_TO_STREAM(expr)                                   \
   {                                                                            \
     auto code = expr;                                                          \
     if (code != PI_SUCCESS) {                                                  \
-      std::cerr << __SYCL_PI_ERROR_REPORT << sycl::detail::codeToString(code)  \
-                << std::endl;                                                  \
+      fprintf(stderr, __SYCL_PI_ERROR_REPORT "%s\n",                           \
+              sycl::detail::codeToString(code).c_str());                       \
+      fflush(stderr);                                                          \
     }                                                                          \
   }
 #endif
diff --git a/sycl/include/sycl/detail/device_filter.hpp b/sycl/include/sycl/detail/device_filter.hpp
index 44e4a2d4ff3a9..7cb73362dbd90 100644
--- a/sycl/include/sycl/detail/device_filter.hpp
+++ b/sycl/include/sycl/detail/device_filter.hpp
@@ -12,8 +12,8 @@
 #include <sycl/detail/defines.hpp>
 #include <sycl/info/info_desc.hpp>
 
+#include <iosfwd>
 #include <optional>
-#include <ostream>
 #include <string>
 
 namespace sycl {
@@ -23,11 +23,6 @@ namespace detail {
 // ---------------------------------------
 // ONEAPI_DEVICE_SELECTOR support
 
-template <typename T>
-std::ostream &operator<<(std::ostream &os, std::optional<T> const &opt) {
-  return opt ? os << opt.value() : os << "not set ";
-}
-
 // the ONEAPI_DEVICE_SELECTOR string gets broken down into these targets
 // will will match devices. If the target is negative, such as !opencl:*
 // then matching devices will not be made available to the user.
@@ -77,8 +72,8 @@ struct device_filter {
 
   device_filter(){};
   device_filter(const std::string &FilterString);
-  friend std::ostream &operator<<(std::ostream &Out,
-                                  const device_filter &Filter);
+  __SYCL_EXPORT friend std::ostream &operator<<(std::ostream &Out,
+                                                const device_filter &Filter);
 };
 
 class device_filter_list {
@@ -93,41 +88,10 @@ class device_filter_list {
   bool backendCompatible(backend Backend);
   bool deviceTypeCompatible(info::device_type DeviceType);
   bool deviceNumberCompatible(int DeviceNum);
-  friend std::ostream &operator<<(std::ostream &Out,
-                                  const device_filter_list &List);
+  __SYCL_EXPORT friend std::ostream &operator<<(std::ostream &Out,
+                                                const device_filter_list &List);
 };
 
-inline std::ostream &operator<<(std::ostream &Out,
-                                const device_filter &Filter) {
-  Out << Filter.Backend << ":";
-  if (Filter.DeviceType == info::device_type::host) {
-    Out << "host";
-  } else if (Filter.DeviceType == info::device_type::cpu) {
-    Out << "cpu";
-  } else if (Filter.DeviceType == info::device_type::gpu) {
-    Out << "gpu";
-  } else if (Filter.DeviceType == info::device_type::accelerator) {
-    Out << "accelerator";
-  } else if (Filter.DeviceType == info::device_type::all) {
-    Out << "*";
-  } else {
-    Out << "unknown";
-  }
-  if (Filter.DeviceNum) {
-    Out << ":" << Filter.DeviceNum.value();
-  }
-  return Out;
-}
-
-inline std::ostream &operator<<(std::ostream &Out,
-                                const device_filter_list &List) {
-  for (const device_filter &Filter : List.FilterList) {
-    Out << Filter;
-    Out << ",";
-  }
-  return Out;
-}
-
 } // namespace detail
 } // namespace _V1
 } // namespace sycl
diff --git a/sycl/include/sycl/detail/pi.hpp b/sycl/include/sycl/detail/pi.hpp
index c4ddfe9fd1b44..8b4c5381e30d5 100644
--- a/sycl/include/sycl/detail/pi.hpp
+++ b/sycl/include/sycl/detail/pi.hpp
@@ -20,7 +20,6 @@
 
 #include <cstdint>     // for uint64_t, uint32_t
 #include <memory>      // for shared_ptr
-#include <sstream>     // for operator<<, basic_ostream, string...
 #include <stddef.h>    // for size_t
 #include <string>      // for char_traits, string
 #include <type_traits> // for false_type, true_type
@@ -108,22 +107,6 @@ bool trace(TraceLevel level);
 
 __SYCL_EXPORT void assertion(bool Condition, const char *Message = nullptr);
 
-template <typename T>
-void handleUnknownParamName(const char *functionName, T parameter) {
-  std::stringstream stream;
-  stream << "Unknown parameter " << parameter << " passed to " << functionName
-         << "\n";
-  auto str = stream.str();
-  auto msg = str.c_str();
-  die(msg);
-}
-
-// This macro is used to report invalid enumerators being passed to PI API
-// GetInfo functions. It will print the name of the function that invoked it
-// and the value of the unknown enumerator.
-#define __SYCL_PI_HANDLE_UNKNOWN_PARAM_NAME(parameter)                         \
-  { sycl::detail::pi::handleUnknownParamName(__func__, parameter); }
-
 using PiPlugin = ::pi_plugin;
 using PiResult = ::pi_result;
 using PiPlatform = ::pi_platform;
diff --git a/sycl/include/sycl/exception_list.hpp b/sycl/include/sycl/exception_list.hpp
index 2a0202fa020a9..80467b6e3f524 100644
--- a/sycl/include/sycl/exception_list.hpp
+++ b/sycl/include/sycl/exception_list.hpp
@@ -10,12 +10,11 @@
 
 // 4.9.2 Exception Class Interface
 
-#include <sycl/detail/export.hpp>         // for __SYCL_EXPORT
-#include <sycl/detail/iostream_proxy.hpp> // for cerr
+#include <sycl/detail/export.hpp> // for __SYCL_EXPORT
 
 #include <cstddef>   // for size_t
 #include <exception> // for exception_ptr, exception
-#include <ostream>   // for operator<<, basic_ostream
+#include <iosfwd>    // for operator<<, basic_ostream
 #include <vector>    // for vector
 
 namespace sycl {
@@ -55,20 +54,7 @@ class __SYCL_EXPORT exception_list {
 namespace detail {
 // Default implementation of async_handler used by queue and context when no
 // user-defined async_handler is specified.
-inline void defaultAsyncHandler(exception_list Exceptions) {
-  std::cerr << "Default async_handler caught exceptions:";
-  for (auto &EIt : Exceptions) {
-    try {
-      if (EIt) {
-        std::rethrow_exception(EIt);
-      }
-    } catch (const std::exception &E) {
-      std::cerr << "\n\t" << E.what();
-    }
-  }
-  std::cerr << std::endl;
-  std::terminate();
-}
+__SYCL_EXPORT void defaultAsyncHandler(exception_list Exceptions);
 } // namespace detail
 } // namespace _V1
 } // namespace sycl
diff --git a/sycl/include/sycl/ext/intel/esimd/detail/half_type_traits.hpp b/sycl/include/sycl/ext/intel/esimd/detail/half_type_traits.hpp
index d7c572b4eb5a1..bc9dab1b724d4 100644
--- a/sycl/include/sycl/ext/intel/esimd/detail/half_type_traits.hpp
+++ b/sycl/include/sycl/ext/intel/esimd/detail/half_type_traits.hpp
@@ -14,6 +14,9 @@
 
 #include <sycl/half_type.hpp>
 
+#include <istream>
+#include <ostream>
+
 /// @cond ESIMD_DETAIL
 
 namespace sycl {
diff --git a/sycl/include/sycl/ext/intel/esimd/simd.hpp b/sycl/include/sycl/ext/intel/esimd/simd.hpp
index 4165c282b5ef9..96b3f3ed02dfc 100644
--- a/sycl/include/sycl/ext/intel/esimd/simd.hpp
+++ b/sycl/include/sycl/ext/intel/esimd/simd.hpp
@@ -10,6 +10,8 @@
 
 #pragma once
 
+#include <ostream>
+
 #include <sycl/ext/intel/esimd/detail/simd_mask_impl.hpp>
 #include <sycl/ext/intel/esimd/detail/simd_obj_impl.hpp>
 
@@ -21,10 +23,6 @@
 
 #include <sycl/ext/oneapi/experimental/invoke_simd.hpp>
 
-#ifndef __SYCL_DEVICE_ONLY__
-#include <sycl/detail/iostream_proxy.hpp>
-#endif // __SYCL_DEVICE_ONLY__
-
 namespace sycl {
 inline namespace _V1 {
 namespace ext::intel::esimd {
diff --git a/sycl/include/sycl/half_type.hpp b/sycl/include/sycl/half_type.hpp
index 1dac778320977..1e58be02d6ab2 100644
--- a/sycl/include/sycl/half_type.hpp
+++ b/sycl/include/sycl/half_type.hpp
@@ -8,10 +8,10 @@
 
 #pragma once
 
-#include <sycl/bit_cast.hpp>              // for bit_cast
-#include <sycl/detail/export.hpp>         // for __SYCL_EXPORT
-#include <sycl/detail/iostream_proxy.hpp> // for istream, ostream
-#include <sycl/detail/vector_traits.hpp>  // for vector_alignment
+#include <sycl/bit_cast.hpp>                  // for bit_cast
+#include <sycl/detail/defines_elementary.hpp> // for __has_builtin
+#include <sycl/detail/export.hpp>             // for __SYCL_EXPORT
+#include <sycl/detail/vector_traits.hpp>      // for vector_alignment
 
 #ifdef __SYCL_DEVICE_ONLY__
 #include <sycl/aspects.hpp>
@@ -20,11 +20,12 @@
 #include <cstddef>     // for size_t
 #include <cstdint>     // for uint16_t, uint32_t, uint8_t
 #include <functional>  // for hash
+#include <iosfwd>      // for istream, ostream
 #include <limits>      // for float_denorm_style, float_r...
 #include <string_view> // for hash
 #include <type_traits> // for enable_if_t
 
-#if !defined(__has_builtin) || !__has_builtin(__builtin_expect)
+#if !__has_builtin(__builtin_expect)
 #define __builtin_expect(a, b) (a)
 #endif
 
@@ -32,8 +33,7 @@
 // `constexpr` could work because the implicit conversion from `float` to
 // `_Float16` can be `constexpr`.
 #define __SYCL_CONSTEXPR_HALF constexpr
-#elif __cpp_lib_bit_cast ||                                                    \
-    (defined(__has_builtin) && __has_builtin(__builtin_bit_cast))
+#elif __cpp_lib_bit_cast || __has_builtin(__builtin_bit_cast)
 #define __SYCL_CONSTEXPR_HALF constexpr
 #else
 #define __SYCL_CONSTEXPR_HALF
@@ -531,18 +531,11 @@ class [[__sycl_detail__::__uses_aspects__(aspect::fp16)]] half {
   }
 
   // Operator << and >>
-  inline friend std::ostream &operator<<(std::ostream &O,
-                                         sycl::half const &rhs) {
-    O << static_cast<float>(rhs);
-    return O;
-  }
+  friend __SYCL_EXPORT std::ostream &operator<<(std::ostream &O,
+                                                sycl::half const &rhs);
 
-  inline friend std::istream &operator>>(std::istream &I, sycl::half &rhs) {
-    float ValFloat = 0.0f;
-    I >> ValFloat;
-    rhs = ValFloat;
-    return I;
-  }
+  friend __SYCL_EXPORT std::istream &operator>>(std::istream &I,
+                                                sycl::half &rhs);
 
   template <typename Key> friend struct std::hash;
 
diff --git a/sycl/include/sycl/handler.hpp b/sycl/include/sycl/handler.hpp
index 6d2ff6e8a5a7d..d2210a149d512 100644
--- a/sycl/include/sycl/handler.hpp
+++ b/sycl/include/sycl/handler.hpp
@@ -1176,9 +1176,11 @@ class __SYCL_EXPORT handler {
 
     bool DidAdjust = false;
     auto Adjust = [&](int Dim, size_t Value) {
-      if (this->RangeRoundingTrace())
-        std::cout << "parallel_for range adjusted at dim " << Dim << " from "
-                  << RoundedRange[Dim] << " to " << Value << std::endl;
+      if (this->RangeRoundingTrace()) {
+        printf("parallel_for range adjusted at dim %d from %zu to %zu\n", Dim,
+               RoundedRange[Dim], Value);
+        fflush(stdout);
+      }
       RoundedRange[Dim] = Value;
       DidAdjust = true;
     };
diff --git a/sycl/include/sycl/sycl.hpp b/sycl/include/sycl/sycl.hpp
index 5b55801796e01..274dbea1efb0d 100644
--- a/sycl/include/sycl/sycl.hpp
+++ b/sycl/include/sycl/sycl.hpp
@@ -98,5 +98,5 @@
 #ifndef SYCL2020_CONFORMANT_APIS
 // We used to include those and some code might be reliant on that.
 #include <cmath>
-#include <complex>
+#include <complex> //TODO: remove todo in no_iostream_include test
 #endif
diff --git a/sycl/include/sycl/types.hpp b/sycl/include/sycl/types.hpp
index 6a5857e0ed83b..9f1840064c61d 100644
--- a/sycl/include/sycl/types.hpp
+++ b/sycl/include/sycl/types.hpp
@@ -50,9 +50,9 @@
 #include <cstddef>     // for size_t, NULL, byte
 #include <cstdint>     // for uint8_t, int16_t, int...
 #include <functional>  // for divides, multiplies
+#include <iosfwd>      // for operator<<, basic_ost...
 #include <iterator>    // for pair
 #include <optional>    // for optional
-#include <ostream>     // for operator<<, basic_ost...
 #include <tuple>       // for tuple
 #include <type_traits> // for enable_if_t, is_same
 #include <utility>     // for index_sequence, make_...
diff --git a/sycl/include/syclcompat/device.hpp b/sycl/include/syclcompat/device.hpp
index be02a42aff4cf..e8b653cdb081e 100644
--- a/sycl/include/syclcompat/device.hpp
+++ b/sycl/include/syclcompat/device.hpp
@@ -33,7 +33,7 @@
 
 #include <algorithm>
 #include <cstring>
-#include <iostream>
+#include <iosfwd>
 #include <map>
 #include <mutex>
 #include <set>
@@ -65,11 +65,11 @@ auto exception_handler = [](sycl::exception_list exceptions) {
     try {
       std::rethrow_exception(e);
     } catch (sycl::exception const &e) {
-      std::cerr << "[SYCLcompat] Caught asynchronous SYCL exception:"
-                << std::endl
-                << e.what() << std::endl
-                << "Exception caught at file:" << __FILE__
-                << ", line:" << __LINE__ << std::endl;
+      fprintf(stderr,
+              "[SYCLcompat] Caught asynchronous SYCL exception:\n%s\n"
+              "Exception caught at file:" __FILE__ ", line:" __LINE__ "\n",
+              e.what().c_str());
+      fflush(stderr);
     }
   }
 };
diff --git a/sycl/plugins/level_zero/tracing.cpp b/sycl/plugins/level_zero/tracing.cpp
index 0049c67a61701..396e384881cfc 100644
--- a/sycl/plugins/level_zero/tracing.cpp
+++ b/sycl/plugins/level_zero/tracing.cpp
@@ -12,10 +12,11 @@
 #endif
 
 #include <exception>
+#include <iostream>
 #include <layers/zel_tracing_api.h>
 #include <ze_api.h>
 
-#include <sycl/detail/iostream_proxy.hpp>
+#include <../../source/detail/iostream_proxy.hpp>
 
 constexpr auto ZE_CALL_STREAM_NAME = "sycl.experimental.level_zero.call";
 constexpr auto ZE_DEBUG_STREAM_NAME = "sycl.experimental.level_zero.debug";
diff --git a/sycl/plugins/opencl/pi_opencl.cpp b/sycl/plugins/opencl/pi_opencl.cpp
index b15418f35a3c8..ea78667b53c04 100644
--- a/sycl/plugins/opencl/pi_opencl.cpp
+++ b/sycl/plugins/opencl/pi_opencl.cpp
@@ -18,7 +18,6 @@
 
 #include <pi_opencl.hpp>
 #include <sycl/detail/cl.h>
-#include <sycl/detail/iostream_proxy.hpp>
 #include <sycl/detail/pi.h>
 
 #include <algorithm>
diff --git a/sycl/source/CMakeLists.txt b/sycl/source/CMakeLists.txt
index 1bde471cd67ac..a8ede9817c5e1 100644
--- a/sycl/source/CMakeLists.txt
+++ b/sycl/source/CMakeLists.txt
@@ -160,6 +160,7 @@ set(SYCL_SOURCES
     "backend/level_zero.cpp"
     "backend.cpp"
     "detail/accessor_impl.cpp"
+    "detail/accessor_iterator.cpp"
     "detail/allowlist.cpp"
     "detail/bindless_images.cpp"
     "detail/buffer_impl.cpp"
@@ -217,6 +218,7 @@ set(SYCL_SOURCES
     "detail/util.cpp"
     "detail/xpti_registry.cpp"
     "accessor.cpp"
+    "backend_types.cpp"
     "buffer.cpp"
     "context.cpp"
     "device.cpp"
@@ -224,6 +226,7 @@ set(SYCL_SOURCES
     "event.cpp"
     "exception.cpp"
     "exception_list.cpp"
+    "half_type.cpp"
     "handler.cpp"
     "image.cpp"
     "interop_handle.cpp"
diff --git a/sycl/source/backend_types.cpp b/sycl/source/backend_types.cpp
new file mode 100644
index 0000000000000..97c9ad8f58be4
--- /dev/null
+++ b/sycl/source/backend_types.cpp
@@ -0,0 +1,46 @@
+//==------------------- backend_types.cpp ----------------------------------==//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include <sycl/backend_types.hpp>
+
+#include <ostream>
+
+namespace sycl {
+inline namespace _V1 {
+
+std::ostream &operator<<(std::ostream &Out, backend be) {
+  switch (be) {
+  case backend::host:
+    Out << "host";
+    break;
+  case backend::opencl:
+    Out << "opencl";
+    break;
+  case backend::ext_oneapi_level_zero:
+    Out << "ext_oneapi_level_zero";
+    break;
+  case backend::ext_oneapi_cuda:
+    Out << "ext_oneapi_cuda";
+    break;
+  case backend::ext_intel_esimd_emulator:
+    Out << "ext_intel_esimd_emulator";
+    break;
+  case backend::ext_oneapi_hip:
+    Out << "ext_oneapi_hip";
+    break;
+  case backend::ext_native_cpu:
+    Out << "ext_native_cpu";
+    break;
+  case backend::all:
+    Out << "all";
+  }
+  return Out;
+}
+
+} // namespace _V1
+} // namespace sycl
diff --git a/sycl/source/detail/accessor_iterator.cpp b/sycl/source/detail/accessor_iterator.cpp
new file mode 100644
index 0000000000000..315a45d92b04b
--- /dev/null
+++ b/sycl/source/detail/accessor_iterator.cpp
@@ -0,0 +1,35 @@
+//==---------------- accessor_iterator.cpp - SYCL standard source file -----==//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include <sycl/detail/accessor_iterator.hpp>
+
+#include <ostream>
+
+namespace sycl {
+inline namespace _V1 {
+
+namespace detail {
+
+__SYCL_EXPORT std::ostream &operator<<(std::ostream &os,
+                                       const accessor_iterator_data &it) {
+  os << "accessor_iterator {\n";
+  os << "\tMLinearId: " << it.MLinearId << "\n";
+  os << "\tMEnd: " << it.MEnd << "\n";
+  os << "\tMStaticOffset: " << it.MStaticOffset << "\n";
+  os << "\tMPerRowOffset: " << it.MPerRowOffset << "\n";
+  os << "\tMPerSliceOffset: " << it.MPerSliceOffset << "\n";
+  os << "\tMRowSize: " << it.MRowSize << "\n";
+  os << "\tMSliceSize: " << it.MSliceSize << "\n";
+  os << "\tMAccessorIsRanged: " << it.MAccessorIsRanged << "\n";
+  os << "}";
+  return os;
+}
+
+} // namespace detail
+} // namespace _V1
+} // namespace sycl
diff --git a/sycl/source/detail/config.cpp b/sycl/source/detail/config.cpp
index d57f1dade20e8..89a3329fb24c5 100644
--- a/sycl/source/detail/config.cpp
+++ b/sycl/source/detail/config.cpp
@@ -7,9 +7,9 @@
 //===----------------------------------------------------------------------===//
 
 #include <detail/config.hpp>
+#include <detail/iostream_proxy.hpp>
 #include <sycl/detail/common.hpp>
 #include <sycl/detail/defines_elementary.hpp>
-#include <sycl/detail/iostream_proxy.hpp>
 #include <sycl/detail/os_util.hpp>
 
 #include <cstring>
diff --git a/sycl/source/detail/config.hpp b/sycl/source/detail/config.hpp
index 02ce094579df2..53b9028aaa92c 100644
--- a/sycl/source/detail/config.hpp
+++ b/sycl/source/detail/config.hpp
@@ -9,6 +9,7 @@
 #pragma once
 
 #include <detail/global_handler.hpp>
+#include <detail/iostream_proxy.hpp>
 #include <sycl/backend_types.hpp>
 #include <sycl/detail/defines.hpp>
 #include <sycl/detail/device_filter.hpp>
@@ -20,6 +21,7 @@
 #include <array>
 #include <cstdlib>
 #include <mutex>
+#include <ostream>
 #include <string>
 #include <utility>
 
diff --git a/sycl/source/detail/device_binary_image.hpp b/sycl/source/detail/device_binary_image.hpp
index b2a74febe392f..e53867122e9bc 100644
--- a/sycl/source/detail/device_binary_image.hpp
+++ b/sycl/source/detail/device_binary_image.hpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 #pragma once
 
+#include <detail/iostream_proxy.hpp>
 #include <sycl/detail/common.hpp>
 #include <sycl/detail/os_util.hpp>
 #include <sycl/detail/pi.hpp>
@@ -14,6 +15,7 @@
 #include <atomic>
 #include <cstring>
 #include <memory>
+#include <ostream>
 
 namespace sycl {
 inline namespace _V1 {
diff --git a/sycl/source/detail/device_filter.cpp b/sycl/source/detail/device_filter.cpp
index 99bbcad3d7a22..c5fb332085158 100644
--- a/sycl/source/detail/device_filter.cpp
+++ b/sycl/source/detail/device_filter.cpp
@@ -19,6 +19,12 @@ namespace sycl {
 inline namespace _V1 {
 namespace detail {
 
+template <class T>
+std::ostream &operator<<(std::ostream &os, std::optional<T> const &opt) {
+  return opt ? os << opt.value() : os << "not set ";
+  return os;
+}
+
 std::vector<std::string_view> tokenize(const std::string_view &Filter,
                                        const std::string &Delim) {
   std::vector<std::string_view> Tokens;
@@ -406,6 +412,37 @@ bool device_filter_list::deviceNumberCompatible(int DeviceNum) {
       });
 }
 
+__SYCL_EXPORT std::ostream &operator<<(std::ostream &Out,
+                                       const device_filter &Filter) {
+  Out << Filter.Backend << ":";
+  if (Filter.DeviceType == info::device_type::host) {
+    Out << "host";
+  } else if (Filter.DeviceType == info::device_type::cpu) {
+    Out << "cpu";
+  } else if (Filter.DeviceType == info::device_type::gpu) {
+    Out << "gpu";
+  } else if (Filter.DeviceType == info::device_type::accelerator) {
+    Out << "accelerator";
+  } else if (Filter.DeviceType == info::device_type::all) {
+    Out << "*";
+  } else {
+    Out << "unknown";
+  }
+  if (Filter.DeviceNum) {
+    Out << ":" << Filter.DeviceNum.value();
+  }
+  return Out;
+}
+
+__SYCL_EXPORT std::ostream &operator<<(std::ostream &Out,
+                                       const device_filter_list &List) {
+  for (const device_filter &Filter : List.FilterList) {
+    Out << Filter;
+    Out << ",";
+  }
+  return Out;
+}
+
 } // namespace detail
 } // namespace _V1
 } // namespace sycl
diff --git a/sycl/source/detail/device_info.hpp b/sycl/source/detail/device_info.hpp
index 0ff49fe7b64f2..989d7e6716a95 100644
--- a/sycl/source/detail/device_info.hpp
+++ b/sycl/source/detail/device_info.hpp
@@ -27,6 +27,7 @@
 #include <sycl/platform.hpp>
 
 #include <chrono>
+#include <sstream>
 #include <thread>
 
 namespace sycl {
diff --git a/sycl/include/sycl/detail/iostream_proxy.hpp b/sycl/source/detail/iostream_proxy.hpp
similarity index 96%
rename from sycl/include/sycl/detail/iostream_proxy.hpp
rename to sycl/source/detail/iostream_proxy.hpp
index 76f432d687d13..847e8017ec4d2 100644
--- a/sycl/include/sycl/detail/iostream_proxy.hpp
+++ b/sycl/source/detail/iostream_proxy.hpp
@@ -8,7 +8,7 @@
 
 #pragma once
 
-#include <istream> // for ostream, istream
+#include <iosfwd> // for ostream, istream
 
 // Hotfix to account for the different namespaces in libstdc++ and libc++
 #ifdef _LIBCPP_BEGIN_NAMESPACE_STD
diff --git a/sycl/source/detail/persistent_device_code_cache.hpp b/sycl/source/detail/persistent_device_code_cache.hpp
index 323d52b859579..ed397f99e7ae5 100644
--- a/sycl/source/detail/persistent_device_code_cache.hpp
+++ b/sycl/source/detail/persistent_device_code_cache.hpp
@@ -11,6 +11,7 @@
 #include <detail/config.hpp>
 #include <detail/device_binary_image.hpp>
 #include <fcntl.h>
+#include <ostream>
 #include <string>
 #include <sycl/detail/os_util.hpp>
 #include <sycl/detail/pi.hpp>
diff --git a/sycl/source/detail/platform_impl.cpp b/sycl/source/detail/platform_impl.cpp
index 7ccbd43771c65..fc3eab70905b0 100644
--- a/sycl/source/detail/platform_impl.cpp
+++ b/sycl/source/detail/platform_impl.cpp
@@ -10,10 +10,10 @@
 #include <detail/config.hpp>
 #include <detail/device_impl.hpp>
 #include <detail/global_handler.hpp>
+#include <detail/iostream_proxy.hpp>
 #include <detail/platform_impl.hpp>
 #include <detail/platform_info.hpp>
 #include <sycl/backend.hpp>
-#include <sycl/detail/iostream_proxy.hpp>
 #include <sycl/detail/util.hpp>
 #include <sycl/device.hpp>
 
diff --git a/sycl/source/detail/plugin.hpp b/sycl/source/detail/plugin.hpp
index 853027bf7c6bb..063e2f2671ebc 100644
--- a/sycl/source/detail/plugin.hpp
+++ b/sycl/source/detail/plugin.hpp
@@ -11,6 +11,7 @@
 #include <detail/plugin_printers.hpp>
 #include <memory>
 #include <mutex>
+#include <ostream>
 #include <sycl/backend_types.hpp>
 #include <sycl/detail/common.hpp>
 #include <sycl/detail/pi.hpp>
diff --git a/sycl/source/detail/plugin_printers.hpp b/sycl/source/detail/plugin_printers.hpp
index 0da8e1c0efc26..c442c573dbde9 100644
--- a/sycl/source/detail/plugin_printers.hpp
+++ b/sycl/source/detail/plugin_printers.hpp
@@ -10,8 +10,10 @@
 
 #pragma once
 
+#include <detail/iostream_proxy.hpp>
 #include <sycl/detail/pi.hpp>
 
+#include <ostream>
 #include <type_traits>
 
 namespace sycl {
diff --git a/sycl/source/detail/posix_pi.cpp b/sycl/source/detail/posix_pi.cpp
index 220727f3bb59a..ed0da13499f26 100644
--- a/sycl/source/detail/posix_pi.cpp
+++ b/sycl/source/detail/posix_pi.cpp
@@ -6,11 +6,12 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include <detail/iostream_proxy.hpp>
 #include <sycl/detail/defines_elementary.hpp>
-#include <sycl/detail/iostream_proxy.hpp>
 #include <sycl/detail/pi.hpp>
 
 #include <dlfcn.h>
+#include <ostream>
 #include <string>
 
 namespace sycl {
diff --git a/sycl/source/detail/spec_constant_impl.cpp b/sycl/source/detail/spec_constant_impl.cpp
index 13fbf9fcc9bdd..f1f615cc213e4 100644
--- a/sycl/source/detail/spec_constant_impl.cpp
+++ b/sycl/source/detail/spec_constant_impl.cpp
@@ -8,8 +8,9 @@
 
 #include <detail/spec_constant_impl.hpp>
 
+#include <detail/iostream_proxy.hpp>
+#include <ostream>
 #include <sycl/detail/defines.hpp>
-#include <sycl/detail/iostream_proxy.hpp>
 #include <sycl/detail/pi.h>
 #include <sycl/detail/util.hpp>
 #include <sycl/exception.hpp>
diff --git a/sycl/source/detail/spec_constant_impl.hpp b/sycl/source/detail/spec_constant_impl.hpp
index b576cc243b542..c629c3380ae93 100644
--- a/sycl/source/detail/spec_constant_impl.hpp
+++ b/sycl/source/detail/spec_constant_impl.hpp
@@ -8,8 +8,8 @@
 
 #pragma once
 
+#include <detail/iostream_proxy.hpp>
 #include <sycl/detail/defines.hpp>
-#include <sycl/detail/iostream_proxy.hpp>
 #include <sycl/detail/util.hpp>
 #include <sycl/stl.hpp>
 
diff --git a/sycl/source/esimd_emulator_device_interface.cpp b/sycl/source/esimd_emulator_device_interface.cpp
index 599ff255976ba..904125ac236a3 100644
--- a/sycl/source/esimd_emulator_device_interface.cpp
+++ b/sycl/source/esimd_emulator_device_interface.cpp
@@ -15,6 +15,8 @@
 ///
 /// \ingroup sycl_pi_esimd_emulator
 
+#include <detail/iostream_proxy.hpp>
+#include <ostream>
 #include <sycl/detail/common.hpp>
 #include <sycl/ext/intel/esimd/emu/detail/esimd_emulator_device_interface.hpp>
 
diff --git a/sycl/source/exception_list.cpp b/sycl/source/exception_list.cpp
index 2b31ec3177501..1a16f4df34f55 100644
--- a/sycl/source/exception_list.cpp
+++ b/sycl/source/exception_list.cpp
@@ -9,6 +9,8 @@
 // 4.9.2 Exception Class Interface
 #include <sycl/exception_list.hpp>
 
+#include <iostream>
+#include <sycl/detail/export.hpp>
 #include <utility>
 
 namespace sycl {
@@ -30,5 +32,24 @@ void exception_list::PushBack(value_type &&Value) {
 
 void exception_list::Clear() noexcept { MList.clear(); }
 
+namespace detail {
+// Default implementation of async_handler used by queue and context when no
+// user-defined async_handler is specified.
+void defaultAsyncHandler(exception_list Exceptions) {
+  std::cerr << "Default async_handler caught exceptions:";
+  for (auto &EIt : Exceptions) {
+    try {
+      if (EIt) {
+        std::rethrow_exception(EIt);
+      }
+    } catch (const std::exception &E) {
+      std::cerr << "\n\t" << E.what();
+    }
+  }
+  std::cerr << std::endl;
+  std::terminate();
+}
+} // namespace detail
+
 } // namespace _V1
 } // namespace sycl
diff --git a/sycl/source/half_type.cpp b/sycl/source/half_type.cpp
new file mode 100644
index 0000000000000..5cf33eb16df84
--- /dev/null
+++ b/sycl/source/half_type.cpp
@@ -0,0 +1,34 @@
+//===--------------- half_type.cpp - SYCL half type -----------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include <sycl/half_type.hpp>
+
+#include <iostream>
+#include <sycl/detail/export.hpp>
+
+namespace sycl {
+inline namespace _V1 {
+namespace detail {
+namespace half_impl {
+
+std::ostream &operator<<(std::ostream &O, half const &rhs) {
+  O << static_cast<float>(rhs);
+  return O;
+}
+
+std::istream &operator>>(std::istream &I, half &rhs) {
+  float ValFloat = 0.0f;
+  I >> ValFloat;
+  rhs = ValFloat;
+  return I;
+}
+
+} // namespace half_impl
+} // namespace detail
+} // namespace _V1
+} // namespace sycl
diff --git a/sycl/source/spirv_ops.cpp b/sycl/source/spirv_ops.cpp
index a635dea89d955..7787d0b5c0f4c 100644
--- a/sycl/source/spirv_ops.cpp
+++ b/sycl/source/spirv_ops.cpp
@@ -8,6 +8,7 @@
 
 #include <CL/__spirv/spirv_ops.hpp>
 #include <detail/platform_util.hpp>
+#include <iostream>
 #include <sycl/exception.hpp>
 
 #include <atomic>
diff --git a/sycl/test/abi/sycl_symbols_linux.dump b/sycl/test/abi/sycl_symbols_linux.dump
index 0ca44740b987f..ea215b131e930 100644
--- a/sycl/test/abi/sycl_symbols_linux.dump
+++ b/sycl/test/abi/sycl_symbols_linux.dump
@@ -3976,6 +3976,7 @@ _ZN4sycl3_V16detail18make_kernel_bundleEmRKNS0_7contextEbNS0_12bundle_stateENS0_
 _ZN4sycl3_V16detail18stringifyErrorCodeEi
 _ZN4sycl3_V16detail19convertChannelOrderE23_pi_image_channel_order
 _ZN4sycl3_V16detail19convertChannelOrderENS0_19image_channel_orderE
+_ZN4sycl3_V16detail19defaultAsyncHandlerENS0_14exception_listE
 _ZN4sycl3_V16detail19getImageElementSizeEhNS0_18image_channel_typeE
 _ZN4sycl3_V16detail19getPluginOpaqueDataILNS0_7backendE5EEEPvS4_
 _ZN4sycl3_V16detail19kernel_bundle_plain32set_specialization_constant_implEPKcPvm
@@ -4034,8 +4035,13 @@ _ZN4sycl3_V16detail6OSUtil12alignedAllocEmm
 _ZN4sycl3_V16detail6OSUtil12getOSMemSizeEv
 _ZN4sycl3_V16detail6OSUtil16getCurrentDSODirB5cxx11Ev
 _ZN4sycl3_V16detail6OSUtil7makeDirEPKc
+_ZN4sycl3_V16detail9half_impllsERSoRKNS2_4halfE
+_ZN4sycl3_V16detail9half_implrsERSiRNS2_4halfE
 _ZN4sycl3_V16detail9join_implERKSt6vectorISt10shared_ptrINS1_18kernel_bundle_implEESaIS5_EENS0_12bundle_stateE
 _ZN4sycl3_V16detail9link_implERKSt6vectorINS0_13kernel_bundleILNS0_12bundle_stateE1EEESaIS5_EERKS2_INS0_6deviceESaISA_EERKNS0_13property_listE
+_ZN4sycl3_V16detaillsERSoRKNS1_13device_filterE
+_ZN4sycl3_V16detaillsERSoRKNS1_18device_filter_listE
+_ZN4sycl3_V16detaillsERSoRKNS1_22accessor_iterator_dataE
 _ZN4sycl3_V16device11get_devicesENS0_4info11device_typeE
 _ZN4sycl3_V16device26ext_oneapi_architecture_isENS0_3ext6oneapi12experimental12architectureE
 _ZN4sycl3_V16device26ext_oneapi_can_access_peerERKS1_NS0_3ext6oneapi11peer_accessE
@@ -4185,6 +4191,7 @@ _ZN4sycl3_V19exceptionD1Ev
 _ZN4sycl3_V19exceptionD2Ev
 _ZN4sycl3_V19kernel_idC1EPKc
 _ZN4sycl3_V19kernel_idC2EPKc
+_ZN4sycl3_V1lsERSoNS0_7backendE
 _ZNK4sycl3_V112cpu_selectorclERKNS0_6deviceE
 _ZNK4sycl3_V112gpu_selectorclERKNS0_6deviceE
 _ZNK4sycl3_V113host_selectorclERKNS0_6deviceE
diff --git a/sycl/test/abi/sycl_symbols_windows.dump b/sycl/test/abi/sycl_symbols_windows.dump
index 1a2a2e42ba08b..e9cffee367a0b 100644
--- a/sycl/test/abi/sycl_symbols_windows.dump
+++ b/sycl/test/abi/sycl_symbols_windows.dump
@@ -775,6 +775,12 @@
 ??4stream_impl@detail@_V1@sycl@@QEAAAEAV0123@$$QEAV0123@@Z
 ??4stream_impl@detail@_V1@sycl@@QEAAAEAV0123@AEBV0123@@Z
 ??4tls_code_loc_t@detail@_V1@sycl@@QEAAAEAV0123@AEBV0123@@Z
+??5half_impl@detail@_V1@sycl@@YAAEAV?$basic_istream@DU?$char_traits@D@std@@@std@@AEAV45@AEAVhalf@0123@@Z
+??6half_impl@detail@_V1@sycl@@YAAEAV?$basic_ostream@DU?$char_traits@D@std@@@std@@AEAV45@AEBVhalf@0123@@Z
+??6_V1@sycl@@YAAEAV?$basic_ostream@DU?$char_traits@D@std@@@std@@AEAV23@W4backend@01@@Z
+??6detail@_V1@sycl@@YAAEAV?$basic_ostream@DU?$char_traits@D@std@@@std@@AEAV34@AEBUaccessor_iterator_data@012@@Z
+??6detail@_V1@sycl@@YAAEAV?$basic_ostream@DU?$char_traits@D@std@@@std@@AEAV34@AEBUdevice_filter@012@@Z
+??6detail@_V1@sycl@@YAAEAV?$basic_ostream@DU?$char_traits@D@std@@@std@@AEAV34@AEBVdevice_filter_list@012@@Z
 ??8context@_V1@sycl@@QEBA_NAEBV012@@Z
 ??8device@_V1@sycl@@QEBA_NAEBV012@@Z
 ??8device_image_plain@detail@_V1@sycl@@QEBA_NAEBV0123@@Z
@@ -974,6 +980,7 @@
 ?create_image@experimental@oneapi@ext@_V1@sycl@@YA?AUunsampled_image_handle@12345@AEAVimage_mem@12345@AEBUimage_descriptor@12345@AEBVqueue@45@@Z
 ?create_image@experimental@oneapi@ext@_V1@sycl@@YA?AUunsampled_image_handle@12345@Uimage_mem_handle@12345@AEBUimage_descriptor@12345@AEBVdevice@45@AEBVcontext@45@@Z
 ?create_image@experimental@oneapi@ext@_V1@sycl@@YA?AUunsampled_image_handle@12345@Uimage_mem_handle@12345@AEBUimage_descriptor@12345@AEBVqueue@45@@Z
+?defaultAsyncHandler@detail@_V1@sycl@@YAXVexception_list@23@@Z
 ?default_selector_v@_V1@sycl@@YAHAEBVdevice@12@@Z
 ?deleteAccProps@buffer_plain@detail@_V1@sycl@@IEAAXAEBW4PropWithDataKind@234@@Z
 ?deleteAccessorProperty@SYCLMemObjT@detail@_V1@sycl@@QEAAXAEBW4PropWithDataKind@234@@Z
diff --git a/sycl/test/basic_tests/accessor/atomic_zero_dimension_accessor.cpp b/sycl/test/basic_tests/accessor/atomic_zero_dimension_accessor.cpp
index ff53db7bf35b3..74ca08de4a20c 100644
--- a/sycl/test/basic_tests/accessor/atomic_zero_dimension_accessor.cpp
+++ b/sycl/test/basic_tests/accessor/atomic_zero_dimension_accessor.cpp
@@ -8,6 +8,8 @@
 
 #include <sycl/sycl.hpp>
 
+#include <iostream>
+
 using namespace sycl;
 
 using atomic_t = sycl::atomic<int>;
diff --git a/sycl/test/basic_tests/accessor/const-type-non-readonly-accessor.cpp b/sycl/test/basic_tests/accessor/const-type-non-readonly-accessor.cpp
index 32c20a0bff257..da3a87b511bb6 100644
--- a/sycl/test/basic_tests/accessor/const-type-non-readonly-accessor.cpp
+++ b/sycl/test/basic_tests/accessor/const-type-non-readonly-accessor.cpp
@@ -2,6 +2,8 @@
 
 #include <sycl/sycl.hpp>
 
+#include <iostream>
+
 using namespace sycl;
 
 constexpr size_t dataSize = 1;
diff --git a/sycl/test/basic_tests/no_iostream_include.cpp b/sycl/test/basic_tests/no_iostream_include.cpp
new file mode 100644
index 0000000000000..c255112cd0965
--- /dev/null
+++ b/sycl/test/basic_tests/no_iostream_include.cpp
@@ -0,0 +1,12 @@
+// RUN: %clangxx -fsycl -fsyntax-only -Xclang -verify -Xclang -verify-ignore-unexpected=note %s
+// Test that only iosfwd and not istream, ostream, and iostream_proxy
+// are included.
+#include <sycl/sycl.hpp>
+
+void t(std::istream &i, std::ostream &o) {
+  char c;
+  i >> c;   // expected-error-todo {{invalid operands to binary expression}}
+  o << o;   // expected-error {{invalid operands to binary expression}}
+  std::cout // expected-error {{no member named 'cout' in namespace 'std'}}
+      << "\n";
+}
diff --git a/sycl/test/basic_tests/types.cpp b/sycl/test/basic_tests/types.cpp
index 4b4738d99f36b..6036946ae0674 100644
--- a/sycl/test/basic_tests/types.cpp
+++ b/sycl/test/basic_tests/types.cpp
@@ -12,6 +12,7 @@
 
 #include <cfloat>
 #include <cstdint>
+#include <iostream>
 #include <type_traits>
 
 using namespace std;
diff --git a/sycl/test/extensions/fpga.cpp b/sycl/test/extensions/fpga.cpp
index b952f00706f80..3df706ea8cebf 100644
--- a/sycl/test/extensions/fpga.cpp
+++ b/sycl/test/extensions/fpga.cpp
@@ -3,6 +3,7 @@
 #include <sycl/ext/intel/fpga_extensions.hpp>
 #include <sycl/sycl.hpp>
 
+#include <iostream>
 #include <type_traits>
 
 namespace intelfpga {
diff --git a/sycl/test/regression/half_host_subnormal_min.cpp b/sycl/test/regression/half_host_subnormal_min.cpp
index f0e0405e879dd..763453ae5f3a2 100644
--- a/sycl/test/regression/half_host_subnormal_min.cpp
+++ b/sycl/test/regression/half_host_subnormal_min.cpp
@@ -6,6 +6,8 @@
 
 #include <sycl/sycl.hpp>
 
+#include <iostream>
+
 int main() {
   sycl::half SubnormalMin =
       sycl::bit_cast<sycl::half>((uint16_t)0b0000000000000001u);
diff --git a/sycl/test/regression/host_half_nextafter.cpp b/sycl/test/regression/host_half_nextafter.cpp
index fe9bf949c65e3..a4e3efefdda4a 100644
--- a/sycl/test/regression/host_half_nextafter.cpp
+++ b/sycl/test/regression/host_half_nextafter.cpp
@@ -6,6 +6,8 @@
 
 #include <sycl/sycl.hpp>
 
+#include <iostream>
+
 void check(uint16_t x, uint16_t y, uint16_t ref) {
   assert(sycl::nextafter(sycl::bit_cast<sycl::half>(x),
                          sycl::bit_cast<sycl::half>(y)) ==
diff --git a/sycl/test/regression/host_tanpi_double_accuracy.cpp b/sycl/test/regression/host_tanpi_double_accuracy.cpp
index d84a391b36e6a..6641c278aa4ef 100644
--- a/sycl/test/regression/host_tanpi_double_accuracy.cpp
+++ b/sycl/test/regression/host_tanpi_double_accuracy.cpp
@@ -6,6 +6,7 @@
 
 #include <cmath>
 #include <iomanip>
+#include <iostream>
 #include <sycl/sycl.hpp>
 
 double get_ulp(double X) {
diff --git a/sycl/unittests/pi/BackendString.hpp b/sycl/unittests/pi/BackendString.hpp
index ea90e3ff3eb54..e5ab476fbbe16 100644
--- a/sycl/unittests/pi/BackendString.hpp
+++ b/sycl/unittests/pi/BackendString.hpp
@@ -5,6 +5,7 @@
 #pragma once
 
 #include <detail/plugin.hpp>
+#include <sstream>
 #include <string>
 
 namespace pi {
diff --git a/sycl/unittests/pi/TestGetPlugin.hpp b/sycl/unittests/pi/TestGetPlugin.hpp
index 774d65c02f420..ef6080cdeddf0 100644
--- a/sycl/unittests/pi/TestGetPlugin.hpp
+++ b/sycl/unittests/pi/TestGetPlugin.hpp
@@ -9,6 +9,7 @@
 #include <detail/plugin.hpp>
 #include <functional>
 #include <optional>
+#include <sstream>
 
 namespace pi {
 inline std::optional<sycl::detail::PluginPtr>