diff --git a/include/fmt/format-inl.h b/include/fmt/format-inl.h
index f4dc1c7c..d0c03b43 100644
--- a/include/fmt/format-inl.h
+++ b/include/fmt/format-inl.h
@@ -2577,10 +2577,10 @@ struct singleton {
   unsigned char lower_count;
 };
 
-FMT_FUNC auto is_printable(uint16_t x, const singleton* singletons,
-                           size_t singletons_size,
-                           const unsigned char* singleton_lowers,
-                           const unsigned char* normal, size_t normal_size)
+inline auto is_printable(uint16_t x, const singleton* singletons,
+                         size_t singletons_size,
+                         const unsigned char* singleton_lowers,
+                         const unsigned char* normal, size_t normal_size)
     -> bool {
   auto upper = x >> 8;
   auto lower_start = 0;
diff --git a/include/fmt/format.h b/include/fmt/format.h
index cf6fc926..d2ba7c9a 100644
--- a/include/fmt/format.h
+++ b/include/fmt/format.h
@@ -1368,7 +1368,7 @@ auto write_ptr(OutputIt out, UIntPtr value,
 }
 
 // Returns true iff the code point cp is printable.
-auto is_printable(uint32_t cp) -> bool;
+FMT_API auto is_printable(uint32_t cp) -> bool;
 
 inline auto needs_escape(uint32_t cp) -> bool {
   return cp < 0x20 || cp == 0x7f || cp == '"' || cp == '\\' ||