Inline functions that return static references must have default visi…

…bility

In rapidsai#833, we gave `rmm::mr::detail::get_map` default visibility.
However, there are a number of other functions that return static
references that should also have this visibility so that the static
reference is unique across multiple DSOs.

- Closes rapidsai#1651

include/rmm/logger.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020-2023, NVIDIA CORPORATION.
+ * Copyright (c) 2020-2024, NVIDIA CORPORATION.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,8 @@
 
 #pragma once
 
+#include <rmm/detail/export.hpp>
+
 #include <fmt/format.h>
 #include <fmt/ostream.h>
 #include <spdlog/sinks/basic_file_sink.h>
@@ -105,7 +107,7 @@ struct bytes {
  *
  * @return spdlog::logger& The logger.
  */
-inline spdlog::logger& logger()
+RMM_EXPORT inline spdlog::logger& logger()
 {
   static detail::logger_wrapper wrapped{};
   return wrapped.logger_;

include/rmm/mr/device/per_device_resource.hpp

@@ -89,14 +89,20 @@ namespace rmm::mr {
 
 namespace detail {
 
+// These symbols must have default visibility so that when they are
+// referenced in multiple different DSOs the linker correctly
+// determines that there is only a single unique reference to the
+// function symbols (and hence they return unique static references
+// across different DSOs).
+// See also https://github.com/rapidsai/rmm/issues/826
 /**
  * @brief Returns a pointer to the initial resource.
  *
  * Returns a global instance of a `cuda_memory_resource` as a function local static.
  *
  * @return Pointer to the static cuda_memory_resource used as the initial, default resource
  */
-inline device_memory_resource* initial_resource()
+RMM_EXPORT inline device_memory_resource* initial_resource()
 {
   static cuda_memory_resource mr{};
   return &mr;
@@ -105,13 +111,12 @@ inline device_memory_resource* initial_resource()
 /**
  * @briefreturn{Reference to the lock}
  */
-inline std::mutex& map_lock()
+RMM_EXPORT inline std::mutex& map_lock()
 {
   static std::mutex map_lock;
   return map_lock;
 }
 
-// This symbol must have default visibility, see: https://github.com/rapidsai/rmm/issues/826
 /**
  * @briefreturn{Reference to the map from device id -> resource}
  */