Apply comments: move implementation to headers

Author: AlexeySachkov

sycl/include/sycl/exception.hpp

@@ -148,6 +148,20 @@ class __SYCL_EXPORT exception : public virtual std::exception {
   friend exception detail::set_pi_error(exception &&e, pi_int32 pi_err);
 };
 
+namespace detail {
+// Even though at the moment those functions are only used in library and not
+// in headers, they were put here in case we will need them to implement some
+// of OpenCL (and other backends) interop APIs to query native backend error
+// from an exception.
+// And we don't want them to be part of our library ABI, because of future
+// underlying changes (PI -> UR -> Offload).
+inline pi_int32 get_pi_error(const exception &e) { return e.MPIErr; }
+inline exception set_pi_error(exception &&e, pi_int32 pi_err) {
+  e.MPIErr = pi_err;
+  return std::move(e);
+}
+} // namespace detail
+
 } // namespace _V1
 } // namespace sycl
 

sycl/source/exception.cpp

@@ -66,12 +66,6 @@ std::error_code make_error_code(sycl::errc Err) noexcept {
 }
 
 namespace detail {
-pi_int32 get_pi_error(const exception &e) { return e.MPIErr; }
-exception set_pi_error(exception &&e, pi_int32 pi_err) {
-  e.MPIErr = pi_err;
-  return std::move(e);
-}
-
 __SYCL_EXPORT const char *stringifyErrorCode(pi_int32 error) {
   switch (error) {
 #define _PI_ERRC(NAME, VAL)                                                    \