win32/HResult: un-inline HResultCategory::message()

src/win32/HResult.cxx

@@ -19,9 +19,24 @@
 
 #include "HResult.hxx"
 
+#include <cassert>
 #include <cstdarg>
+#include <cstdio>
 #include <memory>
 
+std::string
+HResultCategory::message(int Errcode) const
+{
+	const auto msg = HRESULTToString(Errcode);
+	if (!msg.empty())
+		return std::string(msg);
+
+	char buffer[11]; // "0x12345678\0"
+	int size = snprintf(buffer, sizeof(buffer), "0x%1x", Errcode);
+	assert(2 <= size && size <= 10);
+	return std::string(buffer, size);
+}
+
 std::system_error
 FormatHResultError(HRESULT result, const char *fmt, ...) noexcept
 {

src/win32/HResult.hxx

@@ -22,8 +22,6 @@
 
 #include "util/Compiler.h"
 
-#include <cassert>
-#include <cstdio>
 #include <string_view>
 #include <system_error>
 
@@ -66,16 +64,7 @@ static inline const std::error_category &hresult_category() noexcept;
 class HResultCategory : public std::error_category {
 public:
 	const char *name() const noexcept override { return "HRESULT"; }
-	std::string message(int Errcode) const override {
-		const auto msg = HRESULTToString(Errcode);
-		if (!msg.empty()) {
-			return std::string(msg);
-		}
-		char buffer[11]; // "0x12345678\0"
-		int size = snprintf(buffer, sizeof(buffer), "0x%1x", Errcode);
-		assert(2 <= size && size <= 10);
-		return std::string(buffer, size);
-	}
+	std::string message(int Errcode) const override;
 	std::error_condition default_error_condition(int code) const noexcept override {
 		return std::error_condition(code, hresult_category());
 	}