Index: ELF/Error.h
===================================================================
--- ELF/Error.h
+++ ELF/Error.h
@@ -37,8 +37,10 @@
 
 void log(const Twine &Msg);
 void warn(const Twine &Msg);
+void warn(const Twine &Source, const Twine &Msg);
 
 void error(const Twine &Msg);
+void error(const Twine &Source, const Twine &Msg);
 void error(std::error_code EC, const Twine &Prefix);
 
 template <typename T> void error(const ErrorOr<T> &V, const Twine &Prefix) {
Index: ELF/Error.cpp
===================================================================
--- ELF/Error.cpp
+++ ELF/Error.cpp
@@ -27,15 +27,19 @@
     outs() << Argv0 << ": " << Msg << "\n";
 }
 
-void elf::warn(const Twine &Msg) {
+void elf::warn(const Twine &Msg) { warn(Argv0, Msg); }
+
+void elf::warn(const Twine &Source, const Twine &Msg) {
   if (Config->FatalWarnings)
     error(Msg);
   else
-    *ErrorOS << Argv0 << ": warning: " << Msg << "\n";
+    *ErrorOS << Source << ": warning: " << Msg << "\n";
 }
 
-void elf::error(const Twine &Msg) {
-  *ErrorOS << Argv0 << ": error: " << Msg << "\n";
+void elf::error(const Twine &Msg) { error(Argv0, Msg); }
+
+void elf::error(const Twine &Source, const Twine &Msg) {
+  *ErrorOS << Source << ": error: " << Msg << "\n";
   HasError = true;
 }
 
Index: ELF/InputFiles.h
===================================================================
--- ELF/InputFiles.h
+++ ELF/InputFiles.h
@@ -175,6 +175,13 @@
   // R_MIPS_GPREL16 / R_MIPS_GPREL32 relocations.
   uint32_t getMipsGp0() const;
 
+  // Returns name of source file or empty string, if it cannot be fetched.
+  StringRef getSourceFile() { return SourceFile; }
+
+  // Gets symbol which encloses given offset and belong to given section
+  DefinedRegular<ELFT> *getEnclosingSymbol(InputSectionBase<ELFT> *S,
+                                           uintX_t Offset);
+
   // The number is the offset in the string table. It will be used as the
   // st_name of the symbol.
   std::vector<std::pair<const DefinedRegular<ELFT> *, unsigned>> KeptLocalSyms;
@@ -193,6 +200,11 @@
   bool shouldMerge(const Elf_Shdr &Sec);
   SymbolBody *createSymbolBody(const Elf_Sym *Sym);
 
+  // Name of source file obtained from STT_FILE symbol value,
+  // or empty string if there is no such symbol in object file
+  // symbol table.
+  StringRef SourceFile;
+
   // List of all sections defined by this file.
   std::vector<InputSectionBase<ELFT> *> Sections;
 
Index: ELF/InputFiles.cpp
===================================================================
--- ELF/InputFiles.cpp
+++ ELF/InputFiles.cpp
@@ -403,6 +403,20 @@
 }
 
 template <class ELFT>
+DefinedRegular<ELFT> *
+elf::ObjectFile<ELFT>::getEnclosingSymbol(InputSectionBase<ELFT> *S,
+                                          uintX_t Offset) {
+  for (SymbolBody *B : SymbolBodies) {
+    auto *D = dyn_cast<DefinedRegular<ELFT>>(B);
+    if (!D)
+      continue;
+    if (D->Value <= Offset && D->Value + D->Size > Offset && D->Section == S)
+      return D;
+  }
+  return nullptr;
+}
+
+template <class ELFT>
 InputSectionBase<ELFT> *
 elf::ObjectFile<ELFT>::getSection(const Elf_Sym &Sym) const {
   uint32_t Index = this->getSectionIndex(Sym);
@@ -431,6 +445,8 @@
   int Binding = Sym->getBinding();
   InputSectionBase<ELFT> *Sec = getSection(*Sym);
   if (Binding == STB_LOCAL) {
+    if (Sym->getType() == STT_FILE)
+      SourceFile = check(Sym->getName(this->StringTable));
     if (Sym->st_shndx == SHN_UNDEF)
       return new (this->Alloc)
           Undefined(Sym->st_name, Sym->st_other, Sym->getType(), this);
Index: ELF/Relocations.cpp
===================================================================
--- ELF/Relocations.cpp
+++ ELF/Relocations.cpp
@@ -521,7 +521,31 @@
   return Addend;
 }
 
-static void reportUndefined(SymbolBody &Sym) {
+template <class ELFT>
+static std::string getLocation(SymbolBody &Sym, InputSectionBase<ELFT> &S,
+                               typename ELFT::uint Offset) {
+  ObjectFile<ELFT> *File = S.getFile();
+  std::string SrcFile = File->getSourceFile();
+
+  // If don't have STT_FILE typed symbol in object file then
+  // use object file name.
+  if (SrcFile.empty())
+    SrcFile = Sym.File ? getFilename(Sym.File) : getFilename(File);
+
+  DefinedRegular<ELFT> *Encl = File->getEnclosingSymbol(&S, Offset);
+  if (Encl && Encl->Type == STT_FUNC) {
+    StringRef Func = getSymbolName(*File, *Encl);
+    return SrcFile + " (function " +
+           (Config->Demangle ? demangle(Func) : Func.str()) + ")";
+  }
+
+  return (SrcFile + " (" + S.Name + "+0x" + Twine::utohexstr(Offset) + ")")
+      .str();
+}
+
+template <class ELFT>
+static void reportUndefined(SymbolBody &Sym, InputSectionBase<ELFT> &S,
+                            typename ELFT::uint Offset) {
   if (Config->UnresolvedSymbols == UnresolvedPolicy::Ignore)
     return;
 
@@ -529,15 +553,15 @@
       Config->UnresolvedSymbols != UnresolvedPolicy::NoUndef)
     return;
 
-  std::string Msg = "undefined symbol: ";
-  Msg += Config->Demangle ? demangle(Sym.getName()) : Sym.getName().str();
+  std::string Location = getLocation(Sym, S, Offset);
+  std::string Msg =
+      "undefined symbol '" +
+      (Config->Demangle ? demangle(Sym.getName()) : Sym.getName().str()) + "'";
 
-  if (Sym.File)
-    Msg += " in " + getFilename(Sym.File);
   if (Config->UnresolvedSymbols == UnresolvedPolicy::Warn)
-    warn(Msg);
+    warn(Location, Msg);
   else
-    error(Msg);
+    error(Location, Msg);
 }
 
 // The reason we have to do this early scan is as follows
@@ -582,7 +606,7 @@
     // We only report undefined symbols if they are referenced somewhere in the
     // code.
     if (!Body.isLocal() && Body.isUndefined() && !Body.symbol()->isWeak())
-      reportUndefined(Body);
+      reportUndefined(Body, C, RI.r_offset);
 
     RelExpr Expr = Target->getRelExpr(Type, Body);
     bool Preemptible = isPreemptible(Body, Type);
Index: test/ELF/libsearch.s
===================================================================
--- test/ELF/libsearch.s
+++ test/ELF/libsearch.s
@@ -22,7 +22,7 @@
 // Should not link because of undefined symbol _bar
 // RUN: not ld.lld -o %t3 %t.o %tbar.o 2>&1 \
 // RUN:   | FileCheck --check-prefix=UNDEFINED %s
-// UNDEFINED: undefined symbol: _bar
+// UNDEFINED: (.bar+0x0): error: undefined symbol '_bar'
 
 // Should fail if cannot find specified library (without -L switch)
 // RUN: not ld.lld -o %t3 %t.o -lls 2>&1 \
Index: test/ELF/linkerscript/edata-etext.s
===================================================================
--- test/ELF/linkerscript/edata-etext.s
+++ test/ELF/linkerscript/edata-etext.s
@@ -2,9 +2,9 @@
 # RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
 # RUN: echo "SECTIONS { }" > %t.script
 # RUN: not ld.lld %t.o -script %t.script -o %t 2>&1 | FileCheck %s
-# CHECK: undefined symbol: _edata
-# CHECK: undefined symbol: _etext
-# CHECK: undefined symbol: _end
+# CHECK: (.text+0x0): error: undefined symbol '_edata'
+# CHECK: (.text+0x8): error: undefined symbol '_etext'
+# CHECK: (.text+0x10): error: undefined symbol '_end'
 
 .global _start,_end,_etext,_edata
 .text
Index: test/ELF/linkerscript/ehdr_start.s
===================================================================
--- test/ELF/linkerscript/ehdr_start.s
+++ test/ELF/linkerscript/ehdr_start.s
@@ -3,7 +3,7 @@
 # RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t.o
 # RUN: echo "SECTIONS { }" > %t.script
 # RUN: not ld.lld %t.o -script %t.script -o %t 2>&1 | FileCheck %s
-# CHECK: undefined symbol: __ehdr_start
+# CHECK: (.text+0x0): error: undefined symbol '__ehdr_start'
 
 .text
 .global _start, __ehdr_start
Index: test/ELF/lto/combined-lto-object-name.ll
===================================================================
--- test/ELF/lto/combined-lto-object-name.ll
+++ test/ELF/lto/combined-lto-object-name.ll
@@ -11,4 +11,4 @@
   ret void
 }
 
-; CHECK: undefined symbol: foo in {{.*}}combined-lto-object-name.ll.tmp.o
+; CHECK: ld-temp.o (function _start): error: undefined symbol 'foo'
Index: test/ELF/sysroot.s
===================================================================
--- test/ELF/sysroot.s
+++ test/ELF/sysroot.s
@@ -9,7 +9,7 @@
 // Should not link because of undefined symbol _bar
 // RUN: not ld.lld -o %t/r %t/m.o 2>&1 \
 // RUN:     | FileCheck --check-prefix=UNDEFINED %s
-// UNDEFINED: undefined symbol: _bar
+// UNDEFINED: (.text+0x1): error: undefined symbol '_bar'
 
 // We need to be sure that there is no suitable library in the /lib directory
 // RUN: not ld.lld -o %t/r %t/m.o -L/lib -l:libls.a 2>&1 \
Index: test/ELF/tls-static.s
===================================================================
--- test/ELF/tls-static.s
+++ test/ELF/tls-static.s
@@ -10,4 +10,4 @@
 _start:
   call __tls_get_addr
 
-// CHECK: undefined symbol: __tls_get_addr
+// CHECK: (.text+0x1): error: undefined symbol '__tls_get_addr'
Index: test/ELF/undef-shared.s
===================================================================
--- test/ELF/undef-shared.s
+++ test/ELF/undef-shared.s
@@ -1,15 +1,15 @@
 # RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t.o
 # RUN: not ld.lld %t.o -o %t.so -shared 2>&1 | FileCheck %s
 
-# CHECK: undefined symbol: hidden in {{.*}}
+# CHECK: {{.*}} (.data+0x0): error: undefined symbol 'hidden'
 .global hidden
 .hidden hidden
 
-# CHECK: undefined symbol: internal in {{.*}}
+# CHECK: {{.*}} (.data+0x8): error: undefined symbol 'internal'
 .global internal
 .internal internal
 
-# CHECK: undefined symbol: protected in {{.*}}
+# CHECK: {{.*}} (.data+0x10): error: undefined symbol 'protected'
 .global protected
 .protected protected
 
Index: test/ELF/undef.s
===================================================================
--- test/ELF/undef.s
+++ test/ELF/undef.s
@@ -4,14 +4,16 @@
 # RUN: llvm-ar rc %t2.a %t2.o
 # RUN: not ld.lld %t.o %t2.a -o %t.exe 2>&1 | FileCheck %s
 # RUN: not ld.lld -pie %t.o %t2.a -o %t.exe 2>&1 | FileCheck %s
-# CHECK: undefined symbol: foo in
-# CHECK: undefined symbol: bar in
-# CHECK: undefined symbol: foo(int) in
-# CHECK: undefined symbol: zed2 in {{.*}}2.a({{.*}}.o)
+# CHECK: undef.s (.text+0x1): error: undefined symbol 'foo'
+# CHECK: undef.s (.text+0x6): error: undefined symbol 'bar'
+# CHECK: undef.s (.text+0x10): error: undefined symbol 'foo(int)'
+# CHECK: {{.*}}2.a({{.*}}.o) (.text+0x0): error: undefined symbol 'zed2'
 
 # RUN: not ld.lld %t.o %t2.a -o %t.exe -no-demangle 2>&1 | \
 # RUN:   FileCheck -check-prefix=NO-DEMANGLE %s
-# NO-DEMANGLE: undefined symbol: _Z3fooi in
+# NO-DEMANGLE: undef.s (.text+0x10): error: undefined symbol '_Z3fooi'
+
+.file "undef.s"
 
   .globl _start
 _start:
Index: test/ELF/unresolved-symbols.s
===================================================================
--- test/ELF/unresolved-symbols.s
+++ test/ELF/unresolved-symbols.s
@@ -6,7 +6,7 @@
 ## Check that %t2.o contains undefined symbol undef.
 # RUN: not ld.lld %t1.o %t2.o -o %t 2>&1 | \
 # RUN:   FileCheck -check-prefix=UNDCHECK %s
-# UNDCHECK: undefined symbol: undef in {{.*}}2.o
+# UNDCHECK: {{.*}}2.o (.text+0x1): error: undefined symbol 'undef'
 
 ## Error out if unknown option value was set.
 # RUN: not ld.lld %t1.o %t2.o -o %t --unresolved-symbols=xxx 2>&1 | \
@@ -19,7 +19,7 @@
 # RUN: llvm-readobj %t1_1 > /dev/null 2>&1
 # RUN: not ld.lld %t2.o -o %t1_2 --unresolved-symbols=ignore-all --no-undefined 2>&1 | \
 # RUN:   FileCheck -check-prefix=ERRUND %s
-# ERRUND: undefined symbol: undef
+# ERRUND: (.text+0x1): error: undefined symbol 'undef
 ## Also ignore all should not produce error for symbols from DSOs.
 # RUN: ld.lld %t1.o %t.so -o %t1_3 --unresolved-symbols=ignore-all
 # RUN: llvm-readobj %t1_3 > /dev/null 2>&1
Index: test/ELF/verneed-local.s
===================================================================
--- test/ELF/verneed-local.s
+++ test/ELF/verneed-local.s
@@ -2,7 +2,7 @@
 # RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
 # RUN: not ld.lld %t.o %S/Inputs/verneed1.so -o %t 2>&1 | FileCheck %s
 
-# CHECK: undefined symbol: f3 in
+# CHECK: (.text+0x1): error: undefined symbol 'f3'
 .globl _start
 _start:
 call f3
Index: test/ELF/zdefs.s
===================================================================
--- test/ELF/zdefs.s
+++ test/ELF/zdefs.s
@@ -2,6 +2,6 @@
 # RUN: ld.lld -shared %t.o -o %t1.so
 
 # RUN: not ld.lld -z defs -shared %t.o -o %t1.so 2>&1 | FileCheck -check-prefix=ERR %s
-# ERR: undefined symbol: foo
+# ERR: (.text+0x1): error: undefined symbol 'foo'
 
 callq foo@PLT