Driver: generate file lists to pass through to linkers

[abdulras]

Summary

Add support for linker file lists. A file list is similar to linker response
files, but slightly more restricted. A file list may only contain a list of
input files. Flags must remain on the actual command invocation. Runs of files
are collapsed into a single input which is marked as a file list by prepending
the filename with an '@' symbol. The linker will read this file and expand the
contents as the input items.

This is supported by at least the GNU linker as well as Microsoft's link.exe
linker. The use of the option is controlled through a driver flag, defaulting
to disabled.

This functionality aids in reducing the length of the subcommand invoked to
perform the final link. Some systems have a limit on the command line, and when
linking a large number of object files, it is possible to overrun that limit.

[ruiu]

I first thought that GNU and Microsoft linker support a feature called "linker file lists", but they are actually not -- this patch is just to pass input file lists to subcommand using a response file. Is this understanding correct?

I think I don't have an ownership in this area. Hans was workikng on Clang driver, so reassigning to him.

[rnk]

This is a general problem: any subcommand we execute may overflow the system command line length limit. I'd rather solve it transparently for -cc1 as well as linker invocations by exposing a command line length estimate from Support and then estimating our command line length in the driver before invoking the subcommand, optionally with a response file. I know that Sony has an internal patch to do this for -cc1 invocations, so it's not just linker stuff.

[abdulras]

Make getLinkerFileListName more similar to getDependencyFileName. Add an assertion. Tweak some variable names as per review comments.

[abdulras]

ping

[rnk]

Broadly, I'd like to rework this to be more generic. We should have some mechanism in Support to get the max command line length. The driver should have some mechanism for estimating if the command line will overflow that. The Tool should query that, and if it is likely to overflow, go back and put parts of the command into filelists or generic response files. If you really need to support a linker that only supports file lists, then we'll have to change the representation of the command line to be a list of strings that know if they are inputs or flags. That seems OK.

lib/Driver/Tools.cpp

180

Use llvm::raw_fd_ostream. It has less moving parts.

213

This won't be correct for many linkers if the filename contains whitespace. I think we need to know what kind of linker we're calling out to in order to get this right. It's easy for link.exe and gnu ld, since we know exactly how they quote and unquote arguments. See the response file parsing code in llvm/lib/Support/CommandLine.cpp.

[abdulras]

Seems that an alternative implementation has been committed.

include/clang/Basic/DiagnosticDriverKinds.td

 def err_drv_use_of_Z_option : Error<
   "unsupported use of internal gcc -Z option '%0'">;
 def err_drv_output_argument_with_multiple_files : Error<
   "cannot specify -o when generating multiple output files">;
 def err_drv_out_file_argument_with_multiple_sources : Error<
   "cannot specify '%0%1' when compiling multiple source files">;
 def err_no_external_assembler : Error<
   "there is no external assembler that can be used on this platform">;
+def err_drv_unable_to_open_file : Error< "unable to open file: %0">;
 def err_drv_unable_to_remove_file : Error<
   "unable to remove file: %0">;
 def err_drv_command_failure : Error<
   "unable to execute command: %0">;
 def err_drv_invalid_darwin_version : Error<
   "invalid Darwin version number: %0">;
 def err_drv_missing_argument : Error<
   "argument to '%0' is missing (expected %1 value%s1)">;

include/clang/Driver/Options.td

                      Group<f_Group>, HelpText<"Enable the integrated assembler">;
 def fno_integrated_as : Flag<["-"], "fno-integrated-as">,
                         Flags<[CC1Option, DriverOption]>, Group<f_Group>,
                         HelpText<"Disable the integrated assembler">;
 def : Flag<["-"], "integrated-as">, Alias<fintegrated_as>, Flags<[DriverOption]>;
 def : Flag<["-"], "no-integrated-as">, Alias<fno_integrated_as>,
       Flags<[CC1Option, DriverOption]>;
 
+def fuse_linker_response_files : Joined<["-"], "fuse-linker-response-files">;
+
 def working_directory : JoinedOrSeparate<["-"], "working-directory">, Flags<[CC1Option]>,
   HelpText<"Resolve file paths relative to the specified directory">;
 def working_directory_EQ : Joined<["-"], "working-directory=">, Flags<[CC1Option]>,
   Alias<working_directory>;
 
 // Double dash options, which are usually an alias for one of the previous
 // options.
 

lib/Driver/Tools.cpp

 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Format.h"
 #include "llvm/Support/Host.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Process.h"
 #include "llvm/Support/Program.h"
 #include "llvm/Support/raw_ostream.h"
 #include <sys/stat.h>
+#include <fstream>
 
 using namespace clang::driver;
 using namespace clang::driver::tools;
 using namespace clang;
 using namespace llvm::opt;
 
 static void addAssemblerKPIC(const ArgList &Args, ArgStringList &CmdArgs) {
   Arg *LastPICArg = Args.getLastArg(options::OPT_fPIC, options::OPT_fno_PIC,

       CmdArgs.push_back(Args.MakeArgString(std::string(ArgName) + Dirs));
     } else {
       CmdArgs.push_back(ArgName);
       CmdArgs.push_back(Args.MakeArgString(Dirs));
     }
   }
 }
 
-static void AddLinkerInputs(const ToolChain &TC,
+static StringRef GetFileListName(const ArgList &Args,
+                                 const InputInfoList &Inputs, int Sequence) {
+  std::string Buffer;
+  llvm::raw_string_ostream Name(Buffer);
+
+  // Add the prefix so as to ensure that it is made part of the argument string
+  Name << "@";
+
+  if (Arg *Output = Args.getLastArg(options::OPT_o)) {
+    StringRef Value = Output->getValue();
+    Name << Value.substr(0, Value.rfind('.'));
+  } else {
+    Name << Clang::getBaseInputStem(Args, Inputs);
+  }
+
+  Name << Sequence << ".rsp";
+  return Args.MakeArgString(Name.str());
+}
+
+static void AddLinkerInputs(Compilation &C, const ToolChain &TC,
                             const InputInfoList &Inputs, const ArgList &Args,
                             ArgStringList &CmdArgs) {
+  const bool UseLinkerResponseFiles =
+    Args.hasArg(options::OPT_fuse_linker_response_files);
   const Driver &D = TC.getDriver();
 
+  std::ofstream FileList;
+  StringRef FileListName;
+  int FileListSequence = 0;
+
   // Add extra linker input arguments which are not treated as inputs
   // (constructed via -Xarch_).
   Args.AddAllArgValues(CmdArgs, options::OPT_Zlinker_input);
 
   for (const auto &II : Inputs) {
     if (!TC.HasNativeLLVMSupport()) {
       // Don't try to pass LLVM inputs unless we have native support.
       if (II.getType() == types::TY_LLVM_IR ||
           II.getType() == types::TY_LTO_IR ||
           II.getType() == types::TY_LLVM_BC ||
           II.getType() == types::TY_LTO_BC)
         D.Diag(diag::err_drv_no_linker_llvm_support)
           << TC.getTripleString();
     }
 
     // Add filenames immediately.
     if (II.isFilename()) {
-      CmdArgs.push_back(II.getFilename());
+      if (UseLinkerResponseFiles && II.getType() == types::TY_Object) {
+        if (!FileList.is_open()) {
+          FileListName = GetFileListName(Args, Inputs, FileListSequence++);
+
+          // Skip the leading '@'
+          FileList.open(FileListName.substr(1).data(),
+                        std::ios_base::trunc | std::ios_base::out);
+          if (!FileList.is_open())
+            D.Diag(diag::err_drv_unable_to_open_file) << FileListName;
+          C.addTempFile(FileListName.data());
+        }
+        FileList << II.getFilename() << std::endl;
+      } else {
+        if (FileList.is_open()) {
+          FileList.close();
+          CmdArgs.push_back(FileListName.data());
+        }
+        CmdArgs.push_back(II.getFilename());
+      }
       continue;
     }
 
+    if (FileList.is_open()) {
+      FileList.close();
+      CmdArgs.push_back(FileListName.data());
+    }
+
     // Otherwise, this is a linker input argument.
     const Arg &A = II.getInputArg();
 
     // Handle reserved library options.
     if (A.getOption().matches(options::OPT_Z_reserved_lib_stdcxx))
       TC.AddCXXStdlibLibArgs(Args, CmdArgs);
     else if (A.getOption().matches(options::OPT_Z_reserved_lib_cckext))
       TC.AddCCKextLibArgs(Args, CmdArgs);
     else
       A.renderAsInput(Args, CmdArgs);
   }
 
+  // NOTE this is needed here to handle the case where an object file is the
+  // last argument; otherwise, we don't properly close the file list.
+  if (FileList.is_open()) {
+    FileList.close();
+    CmdArgs.push_back(FileListName.data());
+  }
+
   // LIBRARY_PATH - included following the user specified library paths.
   //                and only supported on native toolchains.
   if (!TC.isCrossCompiling())
     addDirectoryList(Args, CmdArgs, "-L", "LIBRARY_PATH");
 }
 
 /// \brief Determine whether Objective-C automated reference counting is
 /// enabled.

   //
   //----------------------------------------------------------------------------
   Args.AddAllArgs(CmdArgs, options::OPT_T_Group);
   Args.AddAllArgs(CmdArgs, options::OPT_e);
   Args.AddAllArgs(CmdArgs, options::OPT_s);
   Args.AddAllArgs(CmdArgs, options::OPT_t);
   Args.AddAllArgs(CmdArgs, options::OPT_u_Group);
 
-  AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs);
+  AddLinkerInputs(C, ToolChain, Inputs, Args, CmdArgs);
 
   //----------------------------------------------------------------------------
   // Libraries
   //----------------------------------------------------------------------------
   if (incStdLib && incDefLibs) {
     if (D.CCCIsCXX()) {
       ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs);
       CmdArgs.push_back("-lm");

     break;
   case LibIOMP5:
     CmdArgs.push_back("-liomp5");
     break;
   case LibUnknown:
     break;
   }
 
-  AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs);
+  AddLinkerInputs(C, getToolChain(), Inputs, Args, CmdArgs);
   
   if (isObjCRuntimeLinked(Args) &&
       !Args.hasArg(options::OPT_nostdlib) &&
       !Args.hasArg(options::OPT_nodefaultlibs)) {
     // We use arclite library for both ARC and subscripting support.
     getMachOToolChain().AddLinkARCArgs(Args, CmdArgs);
 
     CmdArgs.push_back("-framework");

   if (!Args.hasArg(options::OPT_nostdlib) &&
       !Args.hasArg(options::OPT_nostartfiles)) {
     // endfile_spec is empty.
   }
 
   Args.AddAllArgs(CmdArgs, options::OPT_T_Group);
   Args.AddAllArgs(CmdArgs, options::OPT_F);
 
-  const char *Exec =
-    Args.MakeArgString(getToolChain().GetProgramPath("ld"));
+  const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("ld"));
   C.addCommand(new Command(JA, *this, Exec, CmdArgs));
 }
 
 void darwin::Lipo::ConstructJob(Compilation &C, const JobAction &JA,
                                 const InputInfo &Output,
                                 const InputInfoList &Inputs,
                                 const ArgList &Args,
                                 const char *LinkingOutput) const {

 
   CmdArgs.push_back(Args.MakeArgString("-L" + GCCLibPath));
 
   Args.AddAllArgs(CmdArgs, options::OPT_L);
   Args.AddAllArgs(CmdArgs, options::OPT_T_Group);
   Args.AddAllArgs(CmdArgs, options::OPT_e);
   Args.AddAllArgs(CmdArgs, options::OPT_r);
 
-  AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs);
+  AddLinkerInputs(C, getToolChain(), Inputs, Args, CmdArgs);
 
   if (!Args.hasArg(options::OPT_nostdlib) &&
       !Args.hasArg(options::OPT_nodefaultlibs)) {
     if (getToolChain().getDriver().CCCIsCXX())
       getToolChain().AddCXXStdlibLibArgs(Args, CmdArgs);
     CmdArgs.push_back("-lgcc_s");
     if (!Args.hasArg(options::OPT_shared)) {
       CmdArgs.push_back("-lgcc");
       CmdArgs.push_back("-lc");
       CmdArgs.push_back("-lm");
     }
   }
 
   if (!Args.hasArg(options::OPT_nostdlib) &&
       !Args.hasArg(options::OPT_nostartfiles)) {
     CmdArgs.push_back(Args.MakeArgString(GCCLibPath + "crtend.o"));
   }
   CmdArgs.push_back(Args.MakeArgString(LibPath + "crtn.o"));
 
   addProfileRT(getToolChain(), Args, CmdArgs);
 
-  const char *Exec =
-    Args.MakeArgString(getToolChain().GetProgramPath("ld"));
+  const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("ld"));
   C.addCommand(new Command(JA, *this, Exec, CmdArgs));
 }
 
 void auroraux::Assemble::ConstructJob(Compilation &C, const JobAction &JA,
                                       const InputInfo &Output,
                                       const InputInfoList &Inputs,
                                       const ArgList &Args,
                                       const char *LinkingOutput) const {

   CmdArgs.push_back(Args.MakeArgString("-L/opt/gcc4/lib/gcc/"
                                        + getToolChain().getTripleString()
                                        + "/4.2.4"));
 
   Args.AddAllArgs(CmdArgs, options::OPT_L);
   Args.AddAllArgs(CmdArgs, options::OPT_T_Group);
   Args.AddAllArgs(CmdArgs, options::OPT_e);
 
-  AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs);
+  AddLinkerInputs(C, getToolChain(), Inputs, Args, CmdArgs);
 
   if (!Args.hasArg(options::OPT_nostdlib) &&
       !Args.hasArg(options::OPT_nodefaultlibs)) {
     // FIXME: For some reason GCC passes -lgcc before adding
     // the default system libraries. Just mimic this for now.
     CmdArgs.push_back("-lgcc");
 
     if (Args.hasArg(options::OPT_pthread))

   Args.AddAllArgs(CmdArgs, options::OPT_L);
   Args.AddAllArgs(CmdArgs, options::OPT_T_Group);
   Args.AddAllArgs(CmdArgs, options::OPT_e);
   Args.AddAllArgs(CmdArgs, options::OPT_s);
   Args.AddAllArgs(CmdArgs, options::OPT_t);
   Args.AddAllArgs(CmdArgs, options::OPT_Z_Flag);
   Args.AddAllArgs(CmdArgs, options::OPT_r);
 
-  AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs);
+  AddLinkerInputs(C, getToolChain(), Inputs, Args, CmdArgs);
 
   if (!Args.hasArg(options::OPT_nostdlib) &&
       !Args.hasArg(options::OPT_nodefaultlibs)) {
     if (D.CCCIsCXX()) {
       getToolChain().AddCXXStdlibLibArgs(Args, CmdArgs);
       if (Args.hasArg(options::OPT_pg)) 
         CmdArgs.push_back("-lm_p");
       else

                               getToolChain().GetFilePath("crtbeginS.o")));
     }
   }
 
   Args.AddAllArgs(CmdArgs, options::OPT_L);
   Args.AddAllArgs(CmdArgs, options::OPT_T_Group);
   Args.AddAllArgs(CmdArgs, options::OPT_e);
 
-  AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs);
+  AddLinkerInputs(C, getToolChain(), Inputs, Args, CmdArgs);
 
   if (!Args.hasArg(options::OPT_nostdlib) &&
       !Args.hasArg(options::OPT_nodefaultlibs)) {
     if (D.CCCIsCXX()) {
       getToolChain().AddCXXStdlibLibArgs(Args, CmdArgs);
       if (Args.hasArg(options::OPT_pg))
         CmdArgs.push_back("-lm_p");
       else

   Args.AddAllArgs(CmdArgs, options::OPT_s);
   Args.AddAllArgs(CmdArgs, options::OPT_t);
   Args.AddAllArgs(CmdArgs, options::OPT_Z_Flag);
   Args.AddAllArgs(CmdArgs, options::OPT_r);
 
   if (D.IsUsingLTO(Args))
     AddGoldPlugin(ToolChain, Args, CmdArgs);
 
-  AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs);
+  AddLinkerInputs(C, ToolChain, Inputs, Args, CmdArgs);
 
   if (!Args.hasArg(options::OPT_nostdlib) &&
       !Args.hasArg(options::OPT_nodefaultlibs)) {
     if (D.CCCIsCXX()) {
       ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs);
       if (Args.hasArg(options::OPT_pg))
         CmdArgs.push_back("-lm_p");
       else

   Args.AddAllArgs(CmdArgs, options::OPT_L);
   Args.AddAllArgs(CmdArgs, options::OPT_T_Group);
   Args.AddAllArgs(CmdArgs, options::OPT_e);
   Args.AddAllArgs(CmdArgs, options::OPT_s);
   Args.AddAllArgs(CmdArgs, options::OPT_t);
   Args.AddAllArgs(CmdArgs, options::OPT_Z_Flag);
   Args.AddAllArgs(CmdArgs, options::OPT_r);
 
-  AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs);
+  AddLinkerInputs(C, getToolChain(), Inputs, Args, CmdArgs);
 
   unsigned Major, Minor, Micro;
   getToolChain().getTriple().getOSVersion(Major, Minor, Micro);
   bool useLibgcc = true;
   if (Major >= 7 || (Major == 6 && Minor == 99 && Micro >= 40) || Major == 0) {
     switch(getToolChain().getArch()) {
     case llvm::Triple::arm:
     case llvm::Triple::armeb:

     CmdArgs.push_back(Args.MakeArgString(StringRef("-L") + Path));
 
   if (D.IsUsingLTO(Args))
     AddGoldPlugin(ToolChain, Args, CmdArgs);
 
   if (Args.hasArg(options::OPT_Z_Xlinker__no_demangle))
     CmdArgs.push_back("--no-demangle");
 
-  AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs);
+  AddLinkerInputs(C, ToolChain, Inputs, Args, CmdArgs);
 
   addSanitizerRuntimes(getToolChain(), Args, CmdArgs);
   // The profile runtime also needs access to system libraries.
   addProfileRT(getToolChain(), Args, CmdArgs);
 
   if (D.CCCIsCXX() &&
       !Args.hasArg(options::OPT_nostdlib) &&
       !Args.hasArg(options::OPT_nodefaultlibs)) {

       CmdArgs.push_back(Args.MakeArgString(getToolChain().GetFilePath("crtbegin.o")));
       CmdArgs.push_back(Args.MakeArgString(getToolChain().GetFilePath("crtn.o")));
   }
 
   Args.AddAllArgs(CmdArgs, options::OPT_L);
   Args.AddAllArgs(CmdArgs, options::OPT_T_Group);
   Args.AddAllArgs(CmdArgs, options::OPT_e);
 
-  AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs);
+  AddLinkerInputs(C, getToolChain(), Inputs, Args, CmdArgs);
 
   addProfileRT(getToolChain(), Args, CmdArgs);
 
   if (!Args.hasArg(options::OPT_nostdlib) &&
       !Args.hasArg(options::OPT_nodefaultlibs)) {
     if (D.CCCIsCXX()) {
       getToolChain().AddCXXStdlibLibArgs(Args, CmdArgs);
       CmdArgs.push_back("-lm");

       CmdArgs.push_back(Args.MakeArgString(
                               getToolChain().GetFilePath("crtbegin.o")));
   }
 
   Args.AddAllArgs(CmdArgs, options::OPT_L);
   Args.AddAllArgs(CmdArgs, options::OPT_T_Group);
   Args.AddAllArgs(CmdArgs, options::OPT_e);
 
-  AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs);
+  AddLinkerInputs(C, getToolChain(), Inputs, Args, CmdArgs);
 
   if (!Args.hasArg(options::OPT_nostdlib) &&
       !Args.hasArg(options::OPT_nodefaultlibs)) {
     // FIXME: GCC passes on -lgcc, -lgcc_pic and a whole lot of
     //         rpaths
     if (UseGCC47)
       CmdArgs.push_back("-L/usr/lib/gcc47");
     else

 
   if (Args.hasArg(options::OPT_v))
     CmdArgs.push_back("-v");
 
   ExceptionSettings EH = exceptionSettings(Args, getToolChain().getTriple());
   if (EH.ShouldUseExceptionTables)
     CmdArgs.push_back("-fexceptions");
 
-  AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs);
+  AddLinkerInputs(C, getToolChain(), Inputs, Args, CmdArgs);
 
   const char *Exec = Args.MakeArgString(getToolChain().GetProgramPath("xcc"));
   C.addCommand(new Command(JA, *this, Exec, CmdArgs));
 }

test/Driver/filelist.c

+// Test handling of -fuse-linker-response-files
+
+// RUN: %clang -### %S/Inputs/filelist/a.o -o test 2>&1 \
+// RUN:   | FileCheck %s -check-prefix CHECK-NO-FILELIST
+
+// CHECK-NO-FILELIST-NOT: "@test0.rsp"
+// CHECK-NO-FILELIST: "{{.*}}/test/Driver/Inputs/filelist/a.o"
+
+// RUN: %clang -### -fuse-linker-response-files -save-temps %S/Inputs/filelist/a.o -o test 2>&1 \
+// RUN:   | FileCheck %s -check-prefix CHECK-FILELIST
+// RUN: FileCheck -check-prefix CHECK-FILELIST-0 %s < test0.rsp
+
+// CHECK-FILELIST-NOT: "{{.*}}/test/Driver/Inputs/filelist/a.o"
+// CHECK-FILELIST: "@test0.rsp"
+
+// CHECK-FILELIST-0: {{.*}}/test/Driver/Inputs/filelist/a.o
+
+// RUN: %clang -### -fuse-linker-response-files -save-temps %S/Inputs/filelist/a.o -library %S/Inputs/filelist/b.o -o test 2>&1 \
+// RUN:   | FileCheck %s -check-prefix CHECK-FILELIST-SPLIT
+// RUN: FileCheck -check-prefix CHECK-FILELIST-SPLIT-0 %s < test0.rsp
+// RUN: FileCheck -check-prefix CHECK-FILELIST-SPLIT-1 %s < test1.rsp
+
+// CHECK-FILELIST-SPLIT-NOT: "{{.*}}/test/Driver/Inputs/filelist/a.o"
+// CHECK-FILELIST-SPLIT: @test0.rsp
+// CHECK-FILELIST-SPLIT: -library
+// CHECK-FILELIST-SPLIT-NOT: "{{.*}}/test/Driver/Inputs/filelist/b.o"
+// CHECK-FILELIST-SPLIT: @test1.rsp
+
+// CHECK-FILELIST-SPLIT-0: a.o
+
+// CHECK-FILELIST-SPLIT-1: b.o
+
+// RUN: %clang '-###' -fuse-linker-response-files -save-temps %S/Inputs/filelist/a.o %S/Inputs/filelist/c.a %S/Inputs/filelist/b.o -o test 2>&1 \
+// RUN:   | FileCheck %s -check-prefix CHECK-FILELIST-ARCHIVES
+// RUN: FileCheck -check-prefix CHECK-FILELIST-ARCHIVES-0 %s < test0.rsp
+
+// CHECK-FILELIST-ARCHIVES-NOT: "{{.*}}/test/Driver/Inputs/filelist/a.o"
+// CHECK-FILELIST-ARCHIVES-NOT: "{{.*}}/test/Driver/Inputs/filelist/c.a"
+// CHECK-FILELIST-ARCHIVES-NOT: "{{.*}}/test/Driver/Inputs/filelist/b.o"
+// CHECK-FILELIST-ARCHIVES: @test0.rsp
+
+// CHECK-FILELIST-ARCHIVES-0: {{.*}}/test/Driver/Inputs/filelist/a.o
+// CHECK-FILELIST-ARCHIVES-0: {{.*}}/test/Driver/Inputs/filelist/c.a
+// CHECK-FILELIST-ARCHIVES-0: {{.*}}/test/Driver/Inputs/filelist/b.o
+
+// RUN: %clang -### -fuse-linker-response-files -save-temps %S/Inputs/filelist/a.obj -o test 2>&1 \
+// RUN:   | FileCheck %s -check-prefix CHECK-ALT-SUFFIX
+// RUN: FileCheck -check-prefix CHECK-ALT-SUFFIX-0 %s < test0.rsp
+
+// CHECK-ALT-SUFFIX-NOT: "{{.*}}/test/Driver/Inputs/filelist/a.obj"
+// CHECK-ALT-SUFFIX: "@test0.rsp"
+
+// CHECK-ALT-SUFFIX-0: {{.*}}/test/Driver/Inputs/filelist/a.obj
+