From eeb22f825172246c8ff7fc38980b7b0a93d45400 Mon Sep 17 00:00:00 2001
From: Rui Ueyama <ruiu@google.com>
Date: Fri, 25 Sep 2015 15:37:33 +0000
Subject: [PATCH] ELF2: Support reponse files.

http://reviews.llvm.org/D13148

llvm-svn: 248575
---
 lld/ELF/Driver.h        |  3 +++
 lld/ELF/DriverUtils.cpp | 10 +++++++++-
 lld/test/elf2/basic.s   |  5 +++++
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/lld/ELF/Driver.h b/lld/ELF/Driver.h
index 1cc05302038a..8e243d9ac0b3 100644
--- a/lld/ELF/Driver.h
+++ b/lld/ELF/Driver.h
@@ -28,6 +28,9 @@ class ArgParser {
 public:
   // Parses command line options.
   llvm::opt::InputArgList parse(ArrayRef<const char *> Args);
+
+private:
+  llvm::BumpPtrAllocator Alloc;
 };
 
 class LinkerDriver {
diff --git a/lld/ELF/DriverUtils.cpp b/lld/ELF/DriverUtils.cpp
index 8d7ef5e73cfe..704d7c9ec124 100644
--- a/lld/ELF/DriverUtils.cpp
+++ b/lld/ELF/DriverUtils.cpp
@@ -16,6 +16,8 @@
 #include "Driver.h"
 #include "Error.h"
 #include "llvm/ADT/STLExtras.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/StringSaver.h"
 
 using namespace llvm;
 
@@ -53,7 +55,13 @@ opt::InputArgList ArgParser::parse(ArrayRef<const char *> Argv) {
   unsigned MissingIndex;
   unsigned MissingCount;
 
-  opt::InputArgList Args = Table.ParseArgs(Argv, MissingIndex, MissingCount);
+  // Expand response files. '@<filename>' is replaced by the file's contents.
+  SmallVector<const char *, 256> Vec(Argv.data(), Argv.data() + Argv.size());
+  StringSaver Saver(Alloc);
+  llvm::cl::ExpandResponseFiles(Saver, llvm::cl::TokenizeGNUCommandLine, Vec);
+
+  // Parse options and then do error checking.
+  opt::InputArgList Args = Table.ParseArgs(Vec, MissingIndex, MissingCount);
   if (MissingCount)
     error(Twine("missing arg value for \"") + Args.getArgString(MissingIndex) +
           "\", expected " + Twine(MissingCount) +
diff --git a/lld/test/elf2/basic.s b/lld/test/elf2/basic.s
index 15e7e2fcd26d..55bc61b14b72 100644
--- a/lld/test/elf2/basic.s
+++ b/lld/test/elf2/basic.s
@@ -176,6 +176,11 @@ _start:
 # CHECK-NEXT:   }
 # CHECK-NEXT: ]
 
+# RUN: echo " -o %t2" > %t.responsefile
+# RUN: lld -flavor gnu2 %t @%t.responsefile
+# RUN: llvm-readobj -file-headers -sections -program-headers -symbols %t2 \
+# RUN:   | FileCheck %s
+
 # RUN: not lld -flavor gnu2 %t 2>&1 | FileCheck --check-prefix=NO_O %s
 # NO_O: -o must be specified.