[clang] Use SmallString::operator std::string() (NFC)

Author: kazutakahirata

clang/lib/Frontend/CompilerInstance.cpp

@@ -2204,7 +2204,7 @@ void CompilerInstance::createModuleFromSource(SourceLocation ImportLoc,
   // Build the module, inheriting any modules that we've built locally.
   if (compileModuleImpl(*this, ImportLoc, ModuleName, Input, StringRef(),
                         ModuleFileName, PreBuildStep, PostBuildStep)) {
-    BuiltModules[std::string(ModuleName)] = std::string(ModuleFileName.str());
+    BuiltModules[std::string(ModuleName)] = std::string(ModuleFileName);
     llvm::sys::RemoveFileOnSignal(ModuleFileName);
   }
 }

clang/lib/Frontend/Rewrite/FrontendActions.cpp

@@ -77,7 +77,7 @@ class FixItActionSuffixInserter : public FixItOptions {
     SmallString<128> Path(Filename);
     llvm::sys::path::replace_extension(Path,
       NewSuffix + llvm::sys::path::extension(Path));
-    return std::string(Path.str());
+    return std::string(Path);
   }
 };
 

clang/tools/driver/driver.cpp

@@ -64,7 +64,7 @@ std::string GetExecutablePath(const char *Argv0, bool CanonicalPrefixes) {
       if (llvm::ErrorOr<std::string> P =
               llvm::sys::findProgramByName(ExecutablePath))
         ExecutablePath = *P;
-    return std::string(ExecutablePath.str());
+    return std::string(ExecutablePath);
   }
 
   // This just needs to be some symbol in the binary; C++ doesn't