Index: lld/trunk/ELF/Relocations.cpp
===================================================================
--- lld/trunk/ELF/Relocations.cpp
+++ lld/trunk/ELF/Relocations.cpp
@@ -47,6 +47,7 @@
 #include "SymbolTable.h"
 #include "Target.h"
 #include "Thunks.h"
+#include "Strings.h"
 
 #include "llvm/Support/Endian.h"
 #include "llvm/Support/raw_ostream.h"
@@ -519,6 +520,25 @@
   return Addend;
 }
 
+static void reportUndefined(SymbolBody &Sym) {
+  if (Config->UnresolvedSymbols == UnresolvedPolicy::Ignore)
+    return;
+
+  if (Config->Shared && Sym.symbol()->Visibility == STV_DEFAULT &&
+      Config->UnresolvedSymbols != UnresolvedPolicy::NoUndef)
+    return;
+
+  std::string Msg = "undefined symbol: ";
+  Msg += Config->Demangle ? demangle(Sym.getName()) : Sym.getName().str();
+
+  if (Sym.File)
+    Msg += " in " + getFilename(Sym.File);
+  if (Config->UnresolvedSymbols == UnresolvedPolicy::Warn)
+    warn(Msg);
+  else
+    error(Msg);
+}
+
 // The reason we have to do this early scan is as follows
 // * To mmap the output file, we need to know the size
 // * For that, we need to know how many dynamic relocs we will have.
@@ -558,6 +578,10 @@
     SymbolBody &Body = File.getRelocTargetSym(RI);
     uint32_t Type = RI.getType(Config->Mips64EL);
 
+    // We only report undefined symbols if they are referenced somewhere in the code.
+    if (!Body.isLocal() && Body.isUndefined() && !Body.symbol()->isWeak())
+      reportUndefined(Body);
+
     RelExpr Expr = Target->getRelExpr(Type, Body);
     bool Preemptible = isPreemptible(Body, Type);
     Expr = adjustExpr(File, Body, IsWrite, Expr, Type, Buf + RI.r_offset);
Index: lld/trunk/ELF/Writer.cpp
===================================================================
--- lld/trunk/ELF/Writer.cpp
+++ lld/trunk/ELF/Writer.cpp
@@ -307,25 +307,6 @@
     error(EC, "failed to write to the output file");
 }
 
-template <class ELFT> static void reportUndefined(SymbolBody *Sym) {
-  if (Config->UnresolvedSymbols == UnresolvedPolicy::Ignore)
-    return;
-
-  if (Config->Shared && Sym->symbol()->Visibility == STV_DEFAULT &&
-      Config->UnresolvedSymbols != UnresolvedPolicy::NoUndef)
-    return;
-
-  std::string Msg = "undefined symbol: ";
-  Msg += Config->Demangle ? demangle(Sym->getName()) : Sym->getName().str();
-
-  if (Sym->File)
-    Msg += " in " + getFilename(Sym->File);
-  if (Config->UnresolvedSymbols == UnresolvedPolicy::Warn)
-    warn(Msg);
-  else
-    error(Msg);
-}
-
 template <class ELFT>
 static bool shouldKeepInSymtab(InputSectionBase<ELFT> *Sec, StringRef SymName,
                                const SymbolBody &B) {
@@ -819,11 +800,6 @@
   for (Symbol *S : Symtab<ELFT>::X->getSymbols()) {
     SymbolBody *Body = S->body();
 
-    // We only report undefined symbols in regular objects. This means that we
-    // will accept an undefined reference in bitcode if it can be optimized out.
-    if (S->IsUsedInRegularObj && Body->isUndefined() && !S->isWeak())
-      reportUndefined<ELFT>(Body);
-
     if (!includeInSymtab<ELFT>(*Body))
       continue;
     if (Out<ELFT>::SymTab)
Index: lld/trunk/test/ELF/Inputs/use-bar.s
===================================================================
--- lld/trunk/test/ELF/Inputs/use-bar.s
+++ lld/trunk/test/ELF/Inputs/use-bar.s
@@ -0,0 +1,2 @@
+.section .bar,"a"
+ .quad _bar
Index: lld/trunk/test/ELF/libsearch.s
===================================================================
--- lld/trunk/test/ELF/libsearch.s
+++ lld/trunk/test/ELF/libsearch.s
@@ -3,6 +3,8 @@
 // RUN:   %p/Inputs/libsearch-dyn.s -o %tdyn.o
 // RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux \
 // RUN:   %p/Inputs/libsearch-st.s -o %tst.o
+// RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux \
+// RUN:   %p/Inputs/use-bar.s -o %tbar.o
 // RUN: mkdir -p %t.dir
 // RUN: ld.lld -shared %tdyn.o -o %t.dir/libls.so
 // RUN: cp -f %t.dir/libls.so %t.dir/libls2.so
@@ -15,8 +17,10 @@
 // RUN:   | FileCheck --check-prefix=NOLIBRARY %s
 // NOLIBRARY: missing arg value for "-l", expected 1 argument.
 
+// Should link normally, because _bar is not used
+// RUN: ld.lld -o %t3 %t.o
 // Should not link because of undefined symbol _bar
-// RUN: not ld.lld -o %t3 %t.o 2>&1 \
+// RUN: not ld.lld -o %t3 %t.o %tbar.o 2>&1 \
 // RUN:   | FileCheck --check-prefix=UNDEFINED %s
 // UNDEFINED: undefined symbol: _bar
 
Index: lld/trunk/test/ELF/linkerscript/edata-etext.s
===================================================================
--- lld/trunk/test/ELF/linkerscript/edata-etext.s
+++ lld/trunk/test/ELF/linkerscript/edata-etext.s
@@ -3,8 +3,8 @@
 # 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: _end
 # CHECK: undefined symbol: _etext
+# CHECK: undefined symbol: _end
 
 .global _start,_end,_etext,_edata
 .text
Index: lld/trunk/test/ELF/sysroot.s
===================================================================
--- lld/trunk/test/ELF/sysroot.s
+++ lld/trunk/test/ELF/sysroot.s
@@ -34,3 +34,4 @@
 
 .globl _start,_bar
 _start:
+  call _bar
Index: lld/trunk/test/ELF/undef-shared.s
===================================================================
--- lld/trunk/test/ELF/undef-shared.s
+++ lld/trunk/test/ELF/undef-shared.s
@@ -12,3 +12,8 @@
 # CHECK: undefined symbol: protected in {{.*}}
 .global protected
 .protected protected
+
+.section .data, "a"
+ .quad hidden
+ .quad internal
+ .quad protected
Index: lld/trunk/test/ELF/undef.s
===================================================================
--- lld/trunk/test/ELF/undef.s
+++ lld/trunk/test/ELF/undef.s
@@ -4,9 +4,9 @@
 # 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(int) in
-# CHECK: undefined symbol: bar in
 # CHECK: undefined symbol: foo in
+# CHECK: undefined symbol: bar in
+# CHECK: undefined symbol: foo(int) in
 # CHECK: undefined symbol: zed2 in {{.*}}2.a({{.*}}.o)
 
 # RUN: not ld.lld %t.o %t2.a -o %t.exe -no-demangle 2>&1 | \