Index: ELF/Driver.cpp
===================================================================
--- ELF/Driver.cpp
+++ ELF/Driver.cpp
@@ -511,6 +511,7 @@
   Target = TI.get();
   LinkerScript<ELFT> LS;
   Script<ELFT>::X = &LS;
+  ScriptConfig->ExprBridge = &LS;
 
   Config->Rela = ELFT::Is64Bits || Config->EMachine == EM_X86_64;
   Config->Mips64EL =
Index: ELF/LinkerScript.h
===================================================================
--- ELF/LinkerScript.h
+++ ELF/LinkerScript.h
@@ -93,6 +93,11 @@
   unsigned Flags;
 };
 
+class ExpressionsBridge {
+public:
+  virtual uint64_t getSymbolValue(StringRef Sym) = 0;
+};
+
 // ScriptConfiguration holds linker script parse results.
 struct ScriptConfiguration {
   // Used to assign addresses to sections.
@@ -108,12 +113,14 @@
   // List of section patterns specified with KEEP commands. They will
   // be kept even if they are unused and --gc-sections is specified.
   std::vector<StringRef> KeptSections;
+
+  ExpressionsBridge *ExprBridge = nullptr;
 };
 
 extern ScriptConfiguration *ScriptConfig;
 
 // This is a runner of the linker script.
-template <class ELFT> class LinkerScript {
+template <class ELFT> class LinkerScript : public ExpressionsBridge {
   typedef typename ELFT::uint uintX_t;
 
 public:
@@ -130,6 +137,8 @@
   void addScriptedSymbols();
   bool hasPhdrsCommands();
 
+  uint64_t getSymbolValue(StringRef Sym) override;
+
 private:
   // "ScriptConfig" is a bit too long, so define a short name for it.
   ScriptConfiguration &Opt = *ScriptConfig;
Index: ELF/LinkerScript.cpp
===================================================================
--- ELF/LinkerScript.cpp
+++ ELF/LinkerScript.cpp
@@ -369,6 +369,14 @@
   return !Opt.PhdrsCommands.empty();
 }
 
+template <class ELFT>
+uint64_t LinkerScript<ELFT>::getSymbolValue(StringRef Sym) {
+  if (SymbolBody *B = Symtab<ELFT>::X->find(Sym))
+    return B->getVA<ELFT>();
+  error("malformed number: " + Sym);
+  return 0;
+}
+
 // Returns indices of ELF headers containing specific section, identified
 // by Name. Each index is a zero based number of ELF header listed within
 // PHDRS {} script block.
@@ -765,6 +773,10 @@
   return 0;
 }
 
+uint64_t static getSymbolValue(StringRef S) {
+  return ScriptConfig->ExprBridge->getSymbolValue(S);
+}
+
 Expr ScriptParser::readPrimary() {
   StringRef Tok = next();
 
@@ -811,8 +823,11 @@
 
   // Parse a number literal
   uint64_t V = 0;
-  if (Tok.getAsInteger(0, V))
-    setError("malformed number: " + Tok);
+  if (Tok.getAsInteger(0, V)) {
+    if (!isValidCIdentifier(Tok))
+      setError("malformed number: " + Tok);
+    return [=](uint64_t Dot) { return getSymbolValue(Tok); };
+  }
   return [=](uint64_t Dot) { return V; };
 }
 
Index: test/ELF/linkerscript/linkerscript-symbol-assignexpr.s
===================================================================
--- test/ELF/linkerscript/linkerscript-symbol-assignexpr.s
+++ test/ELF/linkerscript/linkerscript-symbol-assignexpr.s
@@ -0,0 +1,25 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t
+
+# RUN: echo "SECTIONS { \
+# RUN:         symbol =  CONSTANT(MAXPAGESIZE); \
+# RUN:         symbol2 = symbol + 0x1234; \
+# RUN:         symbol3 = symbol2; \
+# RUN:       }" > %t.script
+# RUN: ld.lld -o %t1 --script %t.script %t
+# RUN: llvm-objdump -t %t1 | FileCheck %s
+
+# CHECK:      SYMBOL TABLE:
+# CHECK-NEXT: 0000000000000000 *UND* 00000000
+# CHECK-NEXT: 0000000000000120 .text 00000000 _start
+# CHECK-NEXT: 0000000000000121 .text 00000000 foo
+# CHECK-NEXT: 0000000000001000 *ABS* 00000000 symbol
+# CHECK-NEXT: 0000000000002234 *ABS* 00000000 symbol2
+# CHECK-NEXT: 0000000000002234 *ABS* 00000000 symbol3
+
+.global _start
+_start:
+ nop
+
+.global foo
+foo: