Index: ELF/Relocations.cpp
===================================================================
--- ELF/Relocations.cpp
+++ ELF/Relocations.cpp
@@ -878,6 +878,8 @@
     SymbolBody &Body = Sec.getFile<ELFT>()->getRelocTargetSym(Rel);
     RelType Type = Rel.getType(Config->IsMips64EL);
 
+    Body.IsUsedInReloc = true;
+
     // Deal with MIPS oddity.
     if (Config->MipsN32Abi)
       Type = getMipsN32RelType(I, End);
Index: ELF/Symbols.h
===================================================================
--- ELF/Symbols.h
+++ ELF/Symbols.h
@@ -129,6 +129,9 @@
 
   unsigned IsPreemptible : 1;
 
+  // True if this symbol is referenced by some relocation.
+  unsigned IsUsedInReloc : 1;
+
   // The following fields have the same meaning as the ELF symbol attributes.
   uint8_t Type;    // symbol type
   uint8_t StOther; // st_other field value
Index: ELF/Symbols.cpp
===================================================================
--- ELF/Symbols.cpp
+++ ELF/Symbols.cpp
@@ -123,8 +123,8 @@
                        uint8_t Type)
     : SymbolKind(K), IsLocal(IsLocal), NeedsPltAddr(false),
       IsInGlobalMipsGot(false), Is32BitMipsGot(false), IsInIplt(false),
-      IsInIgot(false), IsPreemptible(false), Type(Type), StOther(StOther),
-      Name(Name) {}
+      IsInIgot(false), IsPreemptible(false), IsUsedInReloc(false), Type(Type),
+      StOther(StOther), Name(Name) {}
 
 // Returns true if this is a weak undefined symbol.
 bool SymbolBody::isUndefWeak() const {
Index: ELF/Writer.cpp
===================================================================
--- ELF/Writer.cpp
+++ ELF/Writer.cpp
@@ -1279,6 +1279,11 @@
       InX::SymTab->addSymbol(Body);
 
     if (InX::DynSymTab && S->includeInDynsym()) {
+      if (Body->isUndefined() && !Body->IsUsedInReloc)
+        // This symbol was most probably used in a section, which was collected
+        // in the GC phase. We don't need such symbols in the dynamic symbols
+        // table because they solely introduce useless dependencies.
+        continue;
       InX::DynSymTab->addSymbol(Body);
       if (auto *SS = dyn_cast<SharedSymbol>(Body))
         if (cast<SharedFile<ELFT>>(S->File)->isNeeded())
Index: test/ELF/gc-collect-undefined.s
===================================================================
--- /dev/null
+++ test/ELF/gc-collect-undefined.s
@@ -0,0 +1,18 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t
+# RUN: ld.lld %t -o %tout --gc-sections -shared
+# RUN: llvm-nm -D %tout | FileCheck %s
+
+# CHECK: bar
+# CHECK-NOT: qux
+
+	.global foo,bar,qux
+	.local baz
+
+	.section .data.foo,"aw",%progbits
+foo:
+	.dc.a	bar
+
+	.section .bata.baz,"aw",%progbits
+baz:
+	.dc.a	qux
Index: test/ELF/gnu-hash-table.s
===================================================================
--- test/ELF/gnu-hash-table.s
+++ test/ELF/gnu-hash-table.s
@@ -1,6 +1,6 @@
 # REQUIRES: x86,ppc
 
-# RUN: echo ".globl foo" > %te.s
+# RUN: echo ".globl foo; .data; .dc.a foo" > %te.s
 # RUN: llvm-mc -filetype=obj -triple=i386-pc-linux      %te.s -o %te-i386.o
 # RUN: llvm-mc -filetype=obj -triple=i386-pc-linux      %s    -o %t-i386.o
 # RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux    %s    -o %t-x86_64.o
@@ -244,3 +244,5 @@
 bar:
 .weak zed
 .global xyz
+.data
+    .dc.a  baz
Index: test/ELF/lto/shlib-undefined.ll
===================================================================
--- test/ELF/lto/shlib-undefined.ll
+++ test/ELF/lto/shlib-undefined.ll
@@ -1,6 +1,6 @@
 ; REQUIRES: x86
 ; RUN: llvm-as %s -o %t.o
-; RUN: echo .global __progname > %t2.s
+; RUN: echo ".global __progname; .data; .dc.a __progname" > %t2.s
 ; RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %t2.s -o %t2.o
 ; RUN: ld.lld -shared %t2.o -o %t2.so
 ; RUN: ld.lld -o %t %t.o %t2.so
Index: test/ELF/progname.s
===================================================================
--- test/ELF/progname.s
+++ test/ELF/progname.s
@@ -1,6 +1,6 @@
 // REQUIRES: x86
 // RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
-// RUN: echo .global __progname > %t2.s
+// RUN: echo ".global __progname; .data; .dc.a __progname" > %t2.s
 // RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %t2.s -o %t2.o
 // RUN: ld.lld -shared %t2.o -o %t2.so
 // RUN: ld.lld -o %t %t.o %t2.so
Index: test/ELF/undef-version-script.s
===================================================================
--- test/ELF/undef-version-script.s
+++ test/ELF/undef-version-script.s
@@ -3,9 +3,6 @@
 # RUN: ld.lld --version-script %t.script -shared %t.o -o %t.so
 # RUN: llvm-readobj -dyn-symbols %t.so | FileCheck %s
 
-# This does not match gold's behavior because gold does not create undefined
-# symbols in dynsym without an appropriate (e.g. PLT) relocation in the input.
-
 # CHECK:      DynamicSymbols [
 # CHECK-NEXT:   Symbol {
 # CHECK-NEXT:     Name: @
@@ -38,3 +35,6 @@
 
 .global foo
 .weak bar
+.data
+	.dc.a	foo
+	.dc.a	bar
Index: test/ELF/weak-undef.s
===================================================================
--- test/ELF/weak-undef.s
+++ test/ELF/weak-undef.s
@@ -28,3 +28,6 @@
 
 .globl _start
 _start:
+
+.data
+    .dc.a  foo