From 78e0071f722695fbfeca3b388dad58ec5ed06c76 Mon Sep 17 00:00:00 2001
From: Daniela Engert <dani@ngrt.de>
Date: Tue, 18 Apr 2023 17:12:13 +0200
Subject: [PATCH] export names only once

names declared to be exported at the point of introduction into a namespace *must not* be (re-)declared as exported later in the TU, e.g. when they are redeclared, defined, or specialized. [module.export]/6

Drive-by fix found during module testing: add a missing `detail::` name qualification
---
 include/fmt/args.h    | 2 --
 include/fmt/core.h    | 7 +++----
 include/fmt/ostream.h | 2 +-
 3 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/include/fmt/args.h b/include/fmt/args.h
index a977bf14021e..a3966d140719 100644
--- a/include/fmt/args.h
+++ b/include/fmt/args.h
@@ -59,7 +59,6 @@ class dynamic_arg_list {
   }
 };
 }  // namespace detail
-FMT_BEGIN_EXPORT
 
 /**
   \rst
@@ -230,7 +229,6 @@ class dynamic_format_arg_store
   }
 };
 
-FMT_END_EXPORT
 FMT_END_NAMESPACE
 
 #endif  // FMT_ARGS_H_
diff --git a/include/fmt/core.h b/include/fmt/core.h
index 639fe32ac870..2c6c6cb964e1 100644
--- a/include/fmt/core.h
+++ b/include/fmt/core.h
@@ -1482,7 +1482,6 @@ enum { max_packed_args = 62 / packed_arg_bits };
 enum : unsigned long long { is_unpacked_bit = 1ULL << 63 };
 enum : unsigned long long { has_named_args_bit = 1ULL << 62 };
 }  // namespace detail
-FMT_BEGIN_EXPORT
 
 // An output iterator that appends to a buffer.
 // It is used to reduce symbol sizes for the common case.
@@ -1560,6 +1559,7 @@ template <typename Context> class basic_format_arg {
   ``vis(value)`` will be called with the value of type ``double``.
   \endrst
  */
+FMT_MODULE_EXPORT
 template <typename Visitor, typename Context>
 FMT_CONSTEXPR FMT_INLINE auto visit_format_arg(
     Visitor&& vis, const basic_format_arg<Context>& arg) -> decltype(vis(0)) {
@@ -1601,7 +1601,6 @@ FMT_CONSTEXPR FMT_INLINE auto visit_format_arg(
   return vis(monostate());
 }
 
-FMT_END_EXPORT
 namespace detail {
 
 template <typename Char, typename InputIt>
@@ -1861,6 +1860,7 @@ inline auto arg(const Char* name, const T& arg) -> detail::named_arg<Char, T> {
   static_assert(!detail::is_named_arg<T>(), "nested named arguments");
   return {name, arg};
 }
+FMT_END_EXPORT
 
 /**
   \rst
@@ -1986,7 +1986,7 @@ template <typename Context> class basic_format_args {
 /** An alias to ``basic_format_args<format_context>``. */
 // A separate type would result in shorter symbols but break ABI compatibility
 // between clang and gcc on ARM (#1919).
-using format_args = basic_format_args<format_context>;
+FMT_MODULE_EXPORT using format_args = basic_format_args<format_context>;
 
 // We cannot use enum classes as bit fields because of a gcc bug, so we put them
 // in namespaces instead (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61414).
@@ -2007,7 +2007,6 @@ enum type FMT_ENUM_UNDERLYING_TYPE(unsigned char){none, minus, plus, space};
 }
 using sign_t = sign::type;
 
-FMT_END_EXPORT
 namespace detail {
 
 // Workaround an array initialization issue in gcc 4.8.
diff --git a/include/fmt/ostream.h b/include/fmt/ostream.h
index 3238389d90c9..ce65909b95f0 100644
--- a/include/fmt/ostream.h
+++ b/include/fmt/ostream.h
@@ -111,7 +111,7 @@ struct basic_ostream_formatter : formatter<basic_string_view<Char>, Char> {
   auto format(const T& value, basic_format_context<OutputIt, Char>& ctx) const
       -> OutputIt {
     auto buffer = basic_memory_buffer<Char>();
-    format_value(buffer, value, ctx.locale());
+    detail::format_value(buffer, value, ctx.locale());
     return formatter<basic_string_view<Char>, Char>::format(
         {buffer.data(), buffer.size()}, ctx);
   }