See if __declspec works better for exported friends

apache · Sep 22, 2022 · 8a78d6b · 8a78d6b
1 parent aaf3490
commit 8a78d6b
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Showing 4 changed files with 12 additions and 13 deletions.
diff --git a/cpp/src/arrow/result.h b/cpp/src/arrow/result.h
@@ -94,8 +94,7 @@ ARROW_EXPORT void InvalidValueOrDie(const Status& st);
 ///   arrow::Result<int> CalculateFoo();
 /// ```
 template <class T>
-class [[nodiscard]] Result :  // NOLINT(whitespace/braces)
-                              public util::EqualityComparable<Result<T>> {
+class [[nodiscard]] Result : public util::EqualityComparable<Result<T>> {
   template <typename U>
   friend class Result;
 

diff --git a/cpp/src/arrow/status.h b/cpp/src/arrow/status.h
@@ -129,9 +129,8 @@ class ARROW_EXPORT StatusDetail {
 ///
 /// Additionally, if an error occurred, a specific error message is generally
 /// attached.
-class ARROW_EXPORT [[nodiscard]] Status :  // NOLINT(whitespace/braces)
-                                           public util::EqualityComparable<Status>,
-                                           public util::ToStringOstreamable<Status> {
+class ARROW_EXPORT [[nodiscard]] Status : public util::EqualityComparable<Status>,
+                                          public util::ToStringOstreamable<Status> {
  public:
   // Create a success status.
   Status() noexcept : state_(NULLPTR) {}

diff --git a/cpp/src/arrow/util/future.h b/cpp/src/arrow/util/future.h
@@ -315,7 +315,7 @@ class ARROW_EXPORT FutureImpl : public std::enable_shared_from_this<FutureImpl>
 /// The consumer API allows querying a Future's current state, wait for it
 /// to complete, and composing futures with callbacks.
 template <typename T>
-class [[nodiscard]] Future {  // NOLINT(whitespace/braces)
+class [[nodiscard]] Future {
  public:
   using ValueType = T;
   using SyncType = typename detail::SyncType<T>::type;

diff --git a/cpp/src/arrow/util/visibility.h b/cpp/src/arrow/util/visibility.h
@@ -27,10 +27,10 @@
 #endif
 
 #if defined(__cplusplus) && (defined(__GNUC__) || defined(__clang__))
-// Use C++ attribute syntax when possible to avoid GCC parser bug
+// Use C++ attribute syntax where possible to avoid GCC parser bug
 // (https://stackoverflow.com/questions/57993818/gcc-how-to-combine-attribute-dllexport-and-nodiscard-in-a-struct-de)
-#define ARROW_DLLEXPORT [[gnu::dllexport]]  // NOLINT(whitespace/braces)
-#define ARROW_DLLIMPORT [[gnu::dllimport]]  // NOLINT(whitespace/braces)
+#define ARROW_DLLEXPORT [[gnu::dllexport]]
+#define ARROW_DLLIMPORT [[gnu::dllimport]]
 #else
 #define ARROW_DLLEXPORT __declspec(dllexport)
 #define ARROW_DLLIMPORT __declspec(dllimport)
@@ -42,11 +42,12 @@
 #define ARROW_TEMPLATE_EXPORT
 #elif defined(ARROW_EXPORTING)
 #define ARROW_EXPORT ARROW_DLLEXPORT
-#define ARROW_FRIEND_EXPORT ARROW_DLLEXPORT
+// For some reason [[gnu::dllexport]] doesn't work well with friend declarations
+#define ARROW_FRIEND_EXPORT __declspec(dllexport)
 #define ARROW_TEMPLATE_EXPORT ARROW_DLLEXPORT
 #else
 #define ARROW_EXPORT ARROW_DLLIMPORT
-#define ARROW_FRIEND_EXPORT ARROW_DLLIMPORT
+#define ARROW_FRIEND_EXPORT __declspec(dllimport)
 #define ARROW_TEMPLATE_EXPORT ARROW_DLLIMPORT
 #endif
 
@@ -61,10 +62,10 @@
 
 #if defined(__cplusplus) && (defined(__GNUC__) || defined(__clang__))
 #ifndef ARROW_EXPORT
-#define ARROW_EXPORT [[gnu::visibility("default")]]  // NOLINT(whitespace/braces)
+#define ARROW_EXPORT [[gnu::visibility("default")]]
 #endif
 #ifndef ARROW_NO_EXPORT
-#define ARROW_NO_EXPORT [[gnu::visibility("default")]]  // NOLINT(whitespace/braces)
+#define ARROW_NO_EXPORT [[gnu::visibility("default")]]
 #endif
 #else
 // Not C++, or not gcc/clang