[clang] Don't call raw_string_ostream::flush() (NFC)

Don't call raw_string_ostream::flush(), which is essentially a no-op.
As specified in the docs, raw_string_ostream is always unbuffered

Author: JOE1994

clang/include/clang/AST/StmtDataCollectors.td

@@ -55,7 +55,6 @@ class CallExpr {
           // Add a padding character so that 'foo<X, XX>()' != 'foo<XX, X>()'.
           OS << '\n';
         }
-        OS.flush();
 
         addData(ArgString);
       }

clang/lib/AST/DataCollection.cpp

@@ -41,7 +41,6 @@ std::string getMacroStack(SourceLocation Loc, ASTContext &Context) {
     printMacroName(MacroStackStream, Context, Loc);
     Loc = SM.getImmediateMacroCallerLoc(Loc);
   }
-  MacroStackStream.flush();
   return MacroStack;
 }
 

clang/lib/AST/TemplateName.cpp

@@ -439,6 +439,5 @@ const StreamingDiagnostic &clang::operator<<(const StreamingDiagnostic &DB,
   OS << '\'';
   N.print(OS, PrintingPolicy(LO));
   OS << '\'';
-  OS.flush();
   return DB << NameStr;
 }

clang/lib/Basic/Module.cpp

@@ -252,7 +252,6 @@ std::string Module::getFullModuleName(bool AllowStringLiterals) const {
 
   llvm::raw_string_ostream Out(Result);
   printModuleId(Out, Names.rbegin(), Names.rend(), AllowStringLiterals);
-  Out.flush();
 
   return Result;
 }

clang/lib/CodeGen/BackendUtil.cpp

@@ -352,7 +352,6 @@ static std::string flattenClangCommandLine(ArrayRef<std::string> Args,
     llvm::sys::printArg(OS, Arg, /*Quote=*/true);
     PrintedOneArg = true;
   }
-  OS.flush();
   return FlatCmdLine;
 }
 

clang/lib/CodeGen/CodeGenPGO.cpp

@@ -1134,7 +1134,6 @@ void CodeGenPGO::emitCounterRegionMapping(const Decl *D) {
       *CGM.getCoverageMapping(), CGM.getContext().getSourceManager(),
       CGM.getLangOpts(), RegionCounterMap.get(), RegionMCDCState.get());
   MappingGen.emitCounterMapping(D, OS);
-  OS.flush();
 
   if (CoverageMapping.empty())
     return;
@@ -1155,7 +1154,6 @@ CodeGenPGO::emitEmptyCounterMapping(const Decl *D, StringRef Name,
                                 CGM.getContext().getSourceManager(),
                                 CGM.getLangOpts());
   MappingGen.emitEmptyMapping(D, OS);
-  OS.flush();
 
   if (CoverageMapping.empty())
     return;

clang/lib/Driver/Job.cpp

@@ -343,7 +343,6 @@ int Command::Execute(ArrayRef<std::optional<StringRef>> Redirects,
     writeResponseFile(SS);
     buildArgvForResponseFile(Argv);
     Argv.push_back(nullptr);
-    SS.flush();
 
     // Save the response file in the appropriate encoding
     if (std::error_code EC = writeFileWithEncoding(

clang/lib/Driver/ToolChains/HIPUtility.cpp

@@ -446,7 +446,6 @@ void HIP::constructGenerateObjFileFromHIPFatBinary(
   }
   if (HostTriple.isOSLinux() && HostTriple.isOSBinFormatELF())
     ObjStream << "  .section .note.GNU-stack, \"\", @progbits\n";
-  ObjStream.flush();
 
   // Dump the contents of the temp object file gen if the user requested that.
   // We support this option to enable testing of behavior with -###.

clang/lib/Sema/Sema.cpp

@@ -125,7 +125,6 @@ IdentifierInfo *Sema::InventAbbreviatedTemplateParameterTypeName(
   else
     OS << ParamName->getName() << ":auto";
 
-  OS.flush();
   return &Context.Idents.get(OS.str());
 }
 

clang/lib/Sema/SemaChecking.cpp

@@ -6559,7 +6559,6 @@ CheckFormatHandler::HandleInvalidConversionSpecifier(unsigned argIndex,
       OS << "\\u" << llvm::format("%04x", CodePoint);
     else
       OS << "\\U" << llvm::format("%08x", CodePoint);
-    OS.flush();
     Specifier = CodePointStr;
   }
 

clang/lib/Sema/SemaLookup.cpp

@@ -4880,7 +4880,6 @@ void TypoCorrectionConsumer::NamespaceSpecifierSet::addNameSpecifier(
       SmallVector<const IdentifierInfo *, 4> NewNameSpecifierIdentifiers;
       getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers);
       NNS->print(SpecifierOStream, Context.getPrintingPolicy());
-      SpecifierOStream.flush();
       SameNameSpecifier = NewNameSpecifier == CurNameSpecifier;
     }
     if (SameNameSpecifier || llvm::is_contained(CurContextIdentifiers, Name)) {

clang/lib/Sema/SemaTemplateDeduction.cpp

@@ -5128,7 +5128,6 @@ static bool CheckDeducedPlaceholderConstraints(Sema &S, const AutoType &Type,
           Type.getTypeConstraintConcept()->getTemplateParameters());
     }
     OS << "'";
-    OS.flush();
     S.Diag(TypeLoc.getConceptNameLoc(),
            diag::err_placeholder_constraints_not_satisfied)
         << Deduced << Buf << TypeLoc.getLocalSourceRange();

clang/lib/StaticAnalyzer/Core/CheckerManager.cpp

@@ -669,7 +669,6 @@ void CheckerManager::runCheckersForEvalCall(ExplodedNodeSet &Dst,
           std::string Buf;
           llvm::raw_string_ostream OS(Buf);
           Call.dump(OS);
-          OS.flush();
           return Buf;
         };
         std::string AssertionMessage = llvm::formatv(

clang/lib/Tooling/CommonOptionsParser.cpp

@@ -114,7 +114,6 @@ llvm::Error CommonOptionsParser::init(
   llvm::raw_string_ostream OS(ErrorMessage);
   // Stop initializing if command-line option parsing failed.
   if (!cl::ParseCommandLineOptions(argc, argv, Overview, &OS)) {
-    OS.flush();
     return llvm::make_error<llvm::StringError>(ErrorMessage,
                                                llvm::inconvertibleErrorCode());
   }

clang/lib/Tooling/Core/Replacement.cpp

@@ -605,7 +605,6 @@ llvm::Expected<std::string> applyAllReplacements(StringRef Code,
   std::string Result;
   llvm::raw_string_ostream OS(Result);
   Rewrite.getEditBuffer(ID).write(OS);
-  OS.flush();
   return Result;
 }
 

clang/lib/Tooling/Refactoring/AtomicChange.cpp

@@ -235,7 +235,6 @@ std::string AtomicChange::toYAMLString() {
 
   llvm::yaml::Output YAML(YamlContentStream);
   YAML << *this;
-  YamlContentStream.flush();
   return YamlContent;
 }
 

clang/lib/Tooling/Transformer/Stencil.cpp

@@ -75,7 +75,6 @@ class RawTextStencil : public StencilInterface {
     OS << "\"";
     OS.write_escaped(Text);
     OS << "\"";
-    OS.flush();
     return Result;
   }
 

clang/unittests/Basic/SarifTest.cpp

@@ -35,7 +35,6 @@ static std::string serializeSarifDocument(llvm::json::Object &&Doc) {
   llvm::json::Value Value(std::move(Doc));
   llvm::raw_string_ostream OS{Output};
   OS << llvm::formatv("{0}", Value);
-  OS.flush();
   return Output;
 }
 

clang/unittests/Frontend/TextDiagnosticTest.cpp

@@ -30,7 +30,6 @@ static std::string PrintDiag(const DiagnosticOptions &Opts, FullSourceLoc Loc) {
   // Emit a dummy diagnostic that is just 'message'.
   Diag.emitDiagnostic(Loc, DiagnosticsEngine::Level::Warning, "message",
                       /*Ranges=*/{}, /*FixItHints=*/{});
-  OS.flush();
   return Out;
 }