Any*{Importer,Converter}: no, raw string literals make no sense here.

Test code probably from the time when I didn't know about C string
literal concatenation yet?

src/MagnumPlugins/AnyAudioImporter/Test/AnyAudioImporterTest.cpp

@@ -121,13 +121,16 @@ void AnyImporterTest::detect() {
     std::ostringstream out;
     Error redirectError{&out};
     CORRADE_VERIFY(!importer->openFile(data.filename));
-    /* Can't use raw string literals in macros on GCC 4.8 */
     #ifndef CORRADE_PLUGINMANAGER_NO_DYNAMIC_PLUGIN_SUPPORT
     CORRADE_COMPARE(out.str(), Utility::formatString(
-"PluginManager::Manager::load(): plugin {0} is not static and was not found in nonexistent\nAudio::AnyImporter::openFile(): cannot load the {0} plugin\n", data.plugin));
+        "PluginManager::Manager::load(): plugin {0} is not static and was not found in nonexistent\n"
+        "Audio::AnyImporter::openFile(): cannot load the {0} plugin\n",
+        data.plugin));
     #else
     CORRADE_COMPARE(out.str(), Utility::formatString(
-"PluginManager::Manager::load(): plugin {0} was not found\nAudio::AnyImporter::openFile(): cannot load the {0} plugin\n", data.plugin));
+        "PluginManager::Manager::load(): plugin {0} was not found\n"
+        "Audio::AnyImporter::openFile(): cannot load the {0} plugin\n",
+        data.plugin));
     #endif
 }
 

src/MagnumPlugins/AnyImageImporter/Test/AnyImageImporterTest.cpp

@@ -297,13 +297,16 @@ void AnyImageImporterTest::detect() {
         CORRADE_VERIFY(read);
         CORRADE_VERIFY(!importer->openData(*read));
     } else CORRADE_VERIFY(!importer->openFile(filename));
-    /* Can't use raw string literals in macros on GCC 4.8 */
     #ifndef CORRADE_PLUGINMANAGER_NO_DYNAMIC_PLUGIN_SUPPORT
     CORRADE_COMPARE(out.str(), Utility::formatString(
-"PluginManager::Manager::load(): plugin {0} is not static and was not found in nonexistent\nTrade::AnyImageImporter::{1}(): cannot load the {0} plugin\n", data.plugin, data.asData ? "openData" : "openFile"));
+        "PluginManager::Manager::load(): plugin {0} is not static and was not found in nonexistent\n"
+        "Trade::AnyImageImporter::{1}(): cannot load the {0} plugin\n",
+        data.plugin, data.asData ? "openData" : "openFile"));
     #else
     CORRADE_COMPARE(out.str(), Utility::formatString(
-"PluginManager::Manager::load(): plugin {0} was not found\nTrade::AnyImageImporter::{1}(): cannot load the {0} plugin\n", data.plugin, data.asData ? "openData" : "openFile"));
+        "PluginManager::Manager::load(): plugin {0} was not found\n"
+        "Trade::AnyImageImporter::{1}(): cannot load the {0} plugin\n",
+        data.plugin, data.asData ? "openData" : "openFile"));
     #endif
 }
 

src/MagnumPlugins/AnySceneConverter/Test/AnySceneConverterTest.cpp

@@ -130,13 +130,16 @@ void AnySceneConverterTest::detect() {
     std::ostringstream out;
     Error redirectError{&out};
     CORRADE_VERIFY(!converter->convertToFile(MeshData{MeshPrimitive::Triangles, 0}, data.filename));
-    /* Can't use raw string literals in macros on GCC 4.8 */
     #ifndef CORRADE_PLUGINMANAGER_NO_DYNAMIC_PLUGIN_SUPPORT
     CORRADE_COMPARE(out.str(), Utility::formatString(
-"PluginManager::Manager::load(): plugin {0} is not static and was not found in nonexistent\nTrade::AnySceneConverter::convertToFile(): cannot load the {0} plugin\n", data.plugin));
+        "PluginManager::Manager::load(): plugin {0} is not static and was not found in nonexistent\n"
+        "Trade::AnySceneConverter::convertToFile(): cannot load the {0} plugin\n",
+        data.plugin));
     #else
     CORRADE_COMPARE(out.str(), Utility::formatString(
-"PluginManager::Manager::load(): plugin {0} was not found\nTrade::AnySceneConverter::convertToFile(): cannot load the {0} plugin\n", data.plugin));
+        "PluginManager::Manager::load(): plugin {0} was not found\n"
+        "Trade::AnySceneConverter::convertToFile(): cannot load the {0} plugin\n",
+        data.plugin));
     #endif
 }
 

src/MagnumPlugins/AnySceneImporter/Test/AnySceneImporterTest.cpp

@@ -182,13 +182,16 @@ void AnySceneImporterTest::detect() {
     std::ostringstream out;
     Error redirectError{&out};
     CORRADE_VERIFY(!importer->openFile(data.filename));
-    /* Can't use raw string literals in macros on GCC 4.8 */
     #ifndef CORRADE_PLUGINMANAGER_NO_DYNAMIC_PLUGIN_SUPPORT
     CORRADE_COMPARE(out.str(), Utility::formatString(
-"PluginManager::Manager::load(): plugin {0} is not static and was not found in nonexistent\nTrade::AnySceneImporter::openFile(): cannot load the {0} plugin\n", data.plugin));
+        "PluginManager::Manager::load(): plugin {0} is not static and was not found in nonexistent\n"
+        "Trade::AnySceneImporter::openFile(): cannot load the {0} plugin\n",
+        data.plugin));
     #else
     CORRADE_COMPARE(out.str(), Utility::formatString(
-"PluginManager::Manager::load(): plugin {0} was not found\nTrade::AnySceneImporter::openFile(): cannot load the {0} plugin\n", data.plugin));
+        "PluginManager::Manager::load(): plugin {0} was not found\n"
+        "Trade::AnySceneImporter::openFile(): cannot load the {0} plugin\n",
+        data.plugin));
     #endif
 }