Index: lld/trunk/ELF/Config.h
===================================================================
--- lld/trunk/ELF/Config.h
+++ lld/trunk/ELF/Config.h
@@ -113,6 +113,7 @@
   bool BsymbolicFunctions;
   bool CheckSections;
   bool CompressDebugSections;
+  bool Cref;
   bool DefineCommon;
   bool Demangle = true;
   bool DisableVerify;
Index: lld/trunk/ELF/Driver.cpp
===================================================================
--- lld/trunk/ELF/Driver.cpp
+++ lld/trunk/ELF/Driver.cpp
@@ -618,6 +618,7 @@
       Args.hasFlag(OPT_check_sections, OPT_no_check_sections, true);
   Config->Chroot = Args.getLastArgValue(OPT_chroot);
   Config->CompressDebugSections = getCompressDebugSections(Args);
+  Config->Cref = Args.hasFlag(OPT_cref, OPT_no_cref, false);
   Config->DefineCommon = Args.hasFlag(OPT_define_common, OPT_no_define_common,
                                       !Args.hasArg(OPT_relocatable));
   Config->Demangle = Args.hasFlag(OPT_demangle, OPT_no_demangle, true);
Index: lld/trunk/ELF/MapFile.h
===================================================================
--- lld/trunk/ELF/MapFile.h
+++ lld/trunk/ELF/MapFile.h
@@ -13,6 +13,7 @@
 namespace lld {
 namespace elf {
 void writeMapFile();
+void writeCrossReferenceTable();
 } // namespace elf
 } // namespace lld
 
Index: lld/trunk/ELF/MapFile.cpp
===================================================================
--- lld/trunk/ELF/MapFile.cpp
+++ lld/trunk/ELF/MapFile.cpp
@@ -28,6 +28,8 @@
 #include "SyntheticSections.h"
 #include "lld/Common/Strings.h"
 #include "lld/Common/Threads.h"
+#include "llvm/ADT/MapVector.h"
+#include "llvm/ADT/SetVector.h"
 #include "llvm/Support/raw_ostream.h"
 
 using namespace llvm;
@@ -146,3 +148,50 @@
     }
   }
 }
+
+static void print(StringRef A, StringRef B) {
+  outs() << left_justify(A, 49) << " " << B << "\n";
+}
+
+// Output a cross reference table to stdout. This is for --cref.
+//
+// For each global symbol, we print out a file that defines the symbol
+// followed by files that uses that symbol. Here is an example.
+//
+//     strlen     /lib/x86_64-linux-gnu/libc.so.6
+//                tools/lld/tools/lld/CMakeFiles/lld.dir/lld.cpp.o
+//                lib/libLLVMSupport.a(PrettyStackTrace.cpp.o)
+//
+// In this case, strlen is defined by libc.so.6 and used by other two
+// files.
+void elf::writeCrossReferenceTable() {
+  if (!Config->Cref)
+    return;
+
+  // Collect symbols and files.
+  MapVector<Symbol *, SetVector<InputFile *>> Map;
+  for (InputFile *File : ObjectFiles) {
+    for (Symbol *Sym : File->getSymbols()) {
+      if (isa<SharedSymbol>(Sym))
+        Map[Sym].insert(File);
+      if (auto *D = dyn_cast<Defined>(Sym))
+        if (!D->isLocal() && (!D->Section || D->Section->Live))
+          Map[D].insert(File);
+    }
+  }
+
+  // Print out a header.
+  outs() << "Cross Reference Table\n\n";
+  print("Symbol", "File");
+
+  // Print out a table.
+  for (auto KV : Map) {
+    Symbol *Sym = KV.first;
+    SetVector<InputFile *> &Files = KV.second;
+
+    print(toString(*Sym), toString(Sym->File));
+    for (InputFile *File : Files)
+      if (File != Sym->File)
+        print("", toString(File));
+  }
+}
Index: lld/trunk/ELF/Options.td
===================================================================
--- lld/trunk/ELF/Options.td
+++ lld/trunk/ELF/Options.td
@@ -75,6 +75,10 @@
 def color_diagnostics_eq: J<"color-diagnostics=">,
   HelpText<"Use colors in diagnostics">;
 
+defm cref: B<"cref",
+    "Output cross reference table",
+    "Do not output cross reference table">;
+
 defm define_common: B<"define-common",
     "Assign space to common symbols",
     "Do not assign space to common symbols">;
@@ -420,7 +424,6 @@
 
 // Options listed below are silently ignored for now for compatibility.
 def allow_shlib_undefined: F<"allow-shlib-undefined">;
-def cref: F<"cref">;
 def detect_odr_violations: F<"detect-odr-violations">;
 def g: Flag<["-"], "g">;
 def long_plt: F<"long-plt">;
Index: lld/trunk/ELF/Writer.cpp
===================================================================
--- lld/trunk/ELF/Writer.cpp
+++ lld/trunk/ELF/Writer.cpp
@@ -475,8 +475,9 @@
   if (errorCount())
     return;
 
-  // Handle -Map option.
+  // Handle -Map and -cref options.
   writeMapFile();
+  writeCrossReferenceTable();
   if (errorCount())
     return;
 
Index: lld/trunk/test/ELF/cref.s
===================================================================
--- lld/trunk/test/ELF/cref.s
+++ lld/trunk/test/ELF/cref.s
@@ -0,0 +1,26 @@
+// REQUIRES: x86
+
+// RUN: echo '.global foo; foo:' | llvm-mc -filetype=obj -triple=x86_64-pc-linux - -o %t1.o
+// RUN: echo '.global foo, bar; bar:' | llvm-mc -filetype=obj -triple=x86_64-pc-linux - -o %t2.o
+// RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t3.o
+// RUN: ld.lld -shared -o %t1.so %t1.o -gc-sections
+// RUN: ld.lld -o /dev/null %t1.so %t2.o %t3.o -cref | FileCheck -strict-whitespace %s
+
+//      CHECK: Symbol                                            File
+// CHECK-NEXT: bar                                               {{.*}}2.o
+// CHECK-NEXT:                                                   {{.*}}3.o
+// CHECK-NEXT: foo                                               {{.*}}1.so
+// CHECK-NEXT:                                                   {{.*}}2.o
+// CHECK-NEXT:                                                   {{.*}}3.o
+// CHECK-NEXT: _start                                            {{.*}}3.o
+// CHECK-NEXT: baz                                               {{.*}}3.o
+
+.global _start, foo, bar, baz
+_start:
+  call foo
+  call bar
+localsym:
+baz:
+
+.section .text.a,"ax",@progbits
+discarded:
Index: lld/trunk/test/ELF/silent-ignore.test
===================================================================
--- lld/trunk/test/ELF/silent-ignore.test
+++ lld/trunk/test/ELF/silent-ignore.test
@@ -1,6 +1,5 @@
 RUN: ld.lld --version \
 RUN:   -allow-shlib-undefined \
-RUN:   -cref \
 RUN:   -g \
 RUN:   -no-add-needed \
 RUN:   -no-allow-shlib-undefined \