Index: ELF/Driver.cpp
===================================================================
--- ELF/Driver.cpp
+++ ELF/Driver.cpp
@@ -1018,6 +1018,15 @@
   for (StringRef Sym : Script->Opt.ReferencedSymbols)
     Symtab->addUndefined<ELFT>(Sym);
 
+  // Add dummy symbols defined in linker scripts early because otherwise version
+  // scripts referring script-synthesized symbols wouldn't work due to
+  // undefined symbol error. (Version scripts are processed earlier than linker
+  // scripts.)
+  for (BaseCommand *Base : Script->Opt.Commands)
+    if (SymbolAssignment *Cmd = dyn_cast<SymbolAssignment>(Base))
+      if (Cmd->Name != "." && !Symtab->find(Cmd->Name) && !Cmd->Provide)
+        Symtab->addAbsolute<ELFT>(Cmd->Name, STV_DEFAULT, STB_WEAK);
+
   // If an entry symbol is in a static archive, pull out that file now
   // to complete the symbol table. After this, no new names except a
   // few linker-synthesized ones will be added to the symbol table.
Index: test/ELF/linkerscript/symbols-synthetic.s
===================================================================
--- test/ELF/linkerscript/symbols-synthetic.s
+++ test/ELF/linkerscript/symbols-synthetic.s
@@ -61,6 +61,7 @@
 # SIMPLE-NEXT: 0000000000000120         .foo    00000000 _begin_sec
 # SIMPLE-NEXT: 0000000000000128         *ABS*   00000000 _end_sec_abs
 # SIMPLE-NEXT: 0000000000001048         .text   00000000 _start
+# SIMPLE-NEXT: 0000000000000ee4         *ABS*   00000000 size_foo_3
 # SIMPLE-NEXT: 0000000000000120         .foo    00000000 begin_foo
 # SIMPLE-NEXT: 0000000000000128         .foo    00000000 end_foo
 # SIMPLE-NEXT: 0000000000000008         *ABS*   00000000 size_foo_1
@@ -68,7 +69,6 @@
 # SIMPLE-NEXT: 0000000000001000         .foo    00000000 begin_bar
 # SIMPLE-NEXT: 0000000000001004         .foo    00000000 end_bar
 # SIMPLE-NEXT: 0000000000000ee4         *ABS*   00000000 size_foo_2
-# SIMPLE-NEXT: 0000000000000ee4         *ABS*   00000000 size_foo_3
 # SIMPLE-NEXT: 0000000000001004         .eh_frame_hdr     00000000 __eh_frame_hdr_start
 # SIMPLE-NEXT: 0000000000001010         *ABS*             00000000 __eh_frame_hdr_start2
 # SIMPLE-NEXT: 0000000000001018         .eh_frame_hdr     00000000 __eh_frame_hdr_end
Index: test/ELF/linkerscript/version-script.s
===================================================================
--- test/ELF/linkerscript/version-script.s
+++ test/ELF/linkerscript/version-script.s
@@ -0,0 +1,37 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t.o
+
+# RUN: echo "bar = foo; VERSION { V { global: foo; bar; local: *; }; }" > %t.script
+# RUN: ld.lld -T %t.script -shared --no-undefined-version %t.o -o %t.so
+# RUN: llvm-readobj -V %t.so | FileCheck %s
+
+# CHECK:      Symbols [
+# CHECK-NEXT:   Symbol {
+# CHECK-NEXT:     Version: 0
+# CHECK-NEXT:     Name: @
+# CHECK-NEXT:   }
+# CHECK-NEXT:   Symbol {
+# CHECK-NEXT:     Version: 2
+# CHECK-NEXT:     Name: foo@@V
+# CHECK-NEXT:   }
+# CHECK-NEXT:   Symbol {
+# CHECK-NEXT:     Version: 0
+# CHECK-NEXT:     Name: und@
+# CHECK-NEXT:   }
+# CHECK-NEXT:   Symbol {
+# CHECK-NEXT:     Version: 2
+# CHECK-NEXT:     Name: bar@@V
+# CHECK-NEXT:   }
+# CHECK-NEXT: ]
+
+# RUN: echo "bar = und; VERSION { V { global: foo; bar; local: *; }; }" > %t.script
+# RUN: not ld.lld -T %t.script -shared --no-undefined-version %t.o -o %t.so \
+# RUN:   2>&1 | FileCheck --check-prefix=ERR %s
+# ERR: symbol not found: und
+
+.global und
+
+.text
+.globl foo
+.type foo,@function
+foo: