From: Guillaume Munch <gm@lyx.org>
Date: Sat, 20 Aug 2016 15:05:41 +0000 (+0100)
Subject: Remove unused variable warning and remove preprocessor switch.
X-Git-Tag: 2.3.0alpha1~1111
X-Git-Url: https://git.lyx.org/gitweb/?a=commitdiff_plain;h=193cda6e;p=lyx.git

Remove unused variable warning and remove preprocessor switch.
---

diff --git a/src/graphics/PreviewLoader.cpp b/src/graphics/PreviewLoader.cpp
index e9b1d47202..e1a47e8439 100644
--- a/src/graphics/PreviewLoader.cpp
+++ b/src/graphics/PreviewLoader.cpp
@@ -92,24 +92,15 @@ lyx::Converter const * setConverter(string const & from)
 			return ptr;
 	}
 
-	// Show the error only once
-#ifdef LYX_USE_STD_CALL_ONCE
-	// This is thread-safe.
-	static once_flag flag;
-	call_once(flag, [&](){
-			LYXERR0("PreviewLoader::startLoading()\n"
-			        << "No converter from \"" << from
-			        << "\" format has been defined.");
-		});
-#else
-	// This is also thread-safe according to §6.7.4 of the C++11 standard.
-	static bool once = ([&]{
-			LYXERR0("PreviewLoader::startLoading()\n"
-			        << "No converter from \"" << from
-			        << "\" format has been defined.");
-		} (), true);
-#endif
-	return 0;
+	// Show the error only once. This is thread-safe.
+	static nullptr_t no_conv = [&]{
+		LYXERR0("PreviewLoader::startLoading()\n"
+		        << "No converter from \"" << from
+		        << "\" format has been defined.");
+		return nullptr;
+	} ();
+
+	return no_conv;
 }