[Clang][NFC] Use const auto & to avoid copy (#138069)

shafik · web-flow · commit acc40ed0a747 · 2025-05-01T09:52:09.000-07:00
Static analysis flagged this code as causing a copy when we never modify
ModName and therefore we can use const auto &amp; and avoid copying.
diff --git a/clang/lib/Lex/ModuleMap.cpp b/clang/lib/Lex/ModuleMap.cpp
@@ -1959,7 +1959,7 @@ void ModuleMapLoader::handleExportDecl(const modulemap::ExportDecl &ED) {
 }
 
 void ModuleMapLoader::handleExportAsDecl(const modulemap::ExportAsDecl &EAD) {
-  auto ModName = EAD.Id.front();
+  const auto &ModName = EAD.Id.front();
 
   if (!ActiveModule->ExportAsModule.empty()) {
     if (ActiveModule->ExportAsModule == ModName.first) {

Original file line number	Diff line number	Diff line change
`@@ -1959,7 +1959,7 @@ void ModuleMapLoader::handleExportDecl(const modulemap::ExportDecl &ED) {`
`1959`	`1959`	`}`
`1960`	`1960`
`1961`	`1961`	`void ModuleMapLoader::handleExportAsDecl(const modulemap::ExportAsDecl &EAD) {`
`1962`		`- auto ModName = EAD.Id.front();`
	`1962`	`+ const auto &ModName = EAD.Id.front();`
`1963`	`1963`
`1964`	`1964`	`if (!ActiveModule->ExportAsModule.empty()) {`
`1965`	`1965`	`if (ActiveModule->ExportAsModule == ModName.first) {`