Index: ELF/Config.h
===================================================================
--- ELF/Config.h
+++ ELF/Config.h
@@ -166,7 +166,7 @@
   uint16_t DefaultSymbolVersion = llvm::ELF::VER_NDX_GLOBAL;
   uint16_t EMachine = llvm::ELF::EM_NONE;
   uint64_t ErrorLimit = 20;
-  uint64_t ImageBase;
+  llvm::Optional<uint64_t> ImageBase;
   uint64_t MaxPageSize;
   uint64_t ZStackSize;
   unsigned LTOPartitions;
Index: ELF/Driver.cpp
===================================================================
--- ELF/Driver.cpp
+++ ELF/Driver.cpp
@@ -916,13 +916,12 @@
 }
 
 // Parses -image-base option.
-static uint64_t getImageBase(opt::InputArgList &Args) {
-  // Use default if no -image-base option is given.
-  // Because we are using "Target" here, this function
-  // has to be called after the variable is initialized.
+static Optional<uint64_t> getImageBase(opt::InputArgList &Args) {
+  // Because we are using "Config->MaxPageSize" here, this function has to be
+  // called after the variable is initialized.
   auto *Arg = Args.getLastArg(OPT_image_base);
   if (!Arg)
-    return Config->Pic ? 0 : Target->DefaultImageBase;
+    return None;
 
   StringRef S = Arg->getValue();
   uint64_t V;
Index: ELF/LinkerScript.cpp
===================================================================
--- ELF/LinkerScript.cpp
+++ ELF/LinkerScript.cpp
@@ -365,7 +365,6 @@
   // script parser.
   CurAddressState = State.get();
   CurAddressState->OutSec = Aether;
-  Dot = 0;
 
   for (size_t I = 0; I < Opt.Commands.size(); ++I) {
     // Handle symbol assignments outside of any output section.
@@ -437,7 +436,7 @@
     StartAddr = std::min(StartAddr, KV.second);
 
   auto Expr = [=] {
-    return std::min(StartAddr, Config->ImageBase + elf::getHeaderSize());
+    return std::min(StartAddr, Target->getImageBase() + elf::getHeaderSize());
   };
   Opt.Commands.insert(Opt.Commands.begin(),
                       make<SymbolAssignment>(".", Expr, ""));
@@ -773,9 +772,11 @@
   }
 }
 
+// Assign addresses as instructed by linker script SECTIONS sub-commands.
 void LinkerScript::assignAddresses() {
-  // Assign addresses as instructed by linker script SECTIONS sub-commands.
-  Dot = 0;
+  // By default linker scripts use an initial value of 0 for '.', but prefer
+  // -image-base if set.
+  Dot = Config->ImageBase ? *Config->ImageBase : 0;
   auto State = make_unique<AddressState>(Opt);
   // CurAddressState captures the local AddressState and makes it accessible
   // deliberately. This is needed as there are some cases where we cannot just
Index: ELF/SyntheticSections.cpp
===================================================================
--- ELF/SyntheticSections.cpp
+++ ELF/SyntheticSections.cpp
@@ -1159,7 +1159,7 @@
   if (Config->EMachine == EM_MIPS) {
     add({DT_MIPS_RLD_VERSION, 1});
     add({DT_MIPS_FLAGS, RHF_NOTPOT});
-    add({DT_MIPS_BASE_ADDRESS, Config->ImageBase});
+    add({DT_MIPS_BASE_ADDRESS, Target->getImageBase()});
     add({DT_MIPS_SYMTABNO, InX::DynSymTab->getNumSymbols()});
     add({DT_MIPS_LOCAL_GOTNO, InX::MipsGot->getLocalEntriesNum()});
     if (const SymbolBody *B = InX::MipsGot->getFirstGlobalEntry())
Index: ELF/Target.h
===================================================================
--- ELF/Target.h
+++ ELF/Target.h
@@ -64,11 +64,7 @@
   unsigned PageSize = 4096;
   unsigned DefaultMaxPageSize = 4096;
 
-  // On FreeBSD x86_64 the first page cannot be mmaped.
-  // On Linux that is controled by vm.mmap_min_addr. At least on some x86_64
-  // installs that is 65536, so the first 15 pages cannot be used.
-  // Given that, the smallest value that can be used in here is 0x10000.
-  uint64_t DefaultImageBase = 0x10000;
+  uint64_t getImageBase();
 
   // Offset of _GLOBAL_OFFSET_TABLE_ from base of .got section. Use -1 for
   // end of .got
@@ -108,6 +104,13 @@
   virtual void relaxTlsGdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const;
   virtual void relaxTlsIeToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const;
   virtual void relaxTlsLdToLe(uint8_t *Loc, uint32_t Type, uint64_t Val) const;
+
+protected:
+  // On FreeBSD x86_64 the first page cannot be mmaped.
+  // On Linux that is controled by vm.mmap_min_addr. At least on some x86_64
+  // installs that is 65536, so the first 15 pages cannot be used.
+  // Given that, the smallest value that can be used in here is 0x10000.
+  uint64_t DefaultImageBase = 0x10000;
 };
 
 TargetInfo *getAArch64TargetInfo();
Index: ELF/Target.cpp
===================================================================
--- ELF/Target.cpp
+++ ELF/Target.cpp
@@ -165,3 +165,10 @@
                                 uint64_t Val) const {
   llvm_unreachable("Should not have claimed to be relaxable");
 }
+
+uint64_t TargetInfo::getImageBase() {
+  // Use -image-base if set. Fall back to the target default if not.
+  if (Config->ImageBase)
+    return *Config->ImageBase;
+  return Config->Pic ? 0 : Target->DefaultImageBase;
+}
Index: test/ELF/linkerscript/image-base.s
===================================================================
--- test/ELF/linkerscript/image-base.s
+++ test/ELF/linkerscript/image-base.s
@@ -0,0 +1,18 @@
+# REQUIRES: x86
+
+# RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
+# RUN: echo "SECTIONS { mysym = .; }" > %t.script
+
+# RUN: ld.lld %t.o -o %t-default.elf -T %t.script
+# RUN: llvm-readobj --symbols %t-default.elf | FileCheck %s --check-prefix=DEFAULT
+# DEFAULT: Name: mysym
+# DEFAULT-NEXT: Value: 0x0
+
+# RUN: ld.lld %t.o -o %t-switch.elf -T %t.script --image-base=0x100000
+# RUN: llvm-readobj --symbols %t-switch.elf | FileCheck %s --check-prefix=SWITCH
+# SWITCH: Name: mysym
+# SWITCH-NEXT: Value: 0x100000
+
+.global _start
+_start:
+    nop