Index: ELF/LinkerScript.h
===================================================================
--- ELF/LinkerScript.h
+++ ELF/LinkerScript.h
@@ -41,7 +41,8 @@
 enum SectionsCommandKind {
   AssignmentKind,
   OutputSectionKind,
-  InputSectionKind
+  InputSectionKind,
+  AssertKind
 };
 
 struct BaseCommand {
@@ -96,6 +97,12 @@
   std::vector<StringRef> SectionPatterns;
 };
 
+struct AssertCommand : BaseCommand {
+  AssertCommand(Expr E) : BaseCommand(AssertKind), Expression(E) {}
+  static bool classof(const BaseCommand *C);
+  Expr Expression;
+};
+
 struct PhdrsCommand {
   StringRef Name;
   unsigned Type;
Index: ELF/LinkerScript.cpp
===================================================================
--- ELF/LinkerScript.cpp
+++ ELF/LinkerScript.cpp
@@ -55,6 +55,10 @@
   return C->Kind == InputSectionKind;
 }
 
+bool AssertCommand::classof(const BaseCommand *C) {
+  return C->Kind == AssertKind;
+}
+
 template <class ELFT> static bool isDiscarded(InputSectionBase<ELFT> *S) {
   return !S || !S->Live;
 }
@@ -230,6 +234,11 @@
       continue;
     }
 
+    if (auto *Cmd = dyn_cast<AssertCommand>(Base.get())) {
+      Cmd->Expression(Dot);
+      continue;
+    }
+
     // Find all the sections with required name. There can be more than
     // one section with such name, if the alignment, flags or type
     // attribute differs.
@@ -663,6 +672,11 @@
   Opt.HasContents = true;
   expect("{");
   while (!Error && !skip("}")) {
+    if (peek() == "ASSERT") {
+      Opt.Commands.emplace_back(new AssertCommand(readExpr()));
+      continue;
+    }
+
     StringRef Tok = next();
     if (peek() == "=" || peek() == "+=") {
       readAssignment(Tok);
@@ -981,6 +995,19 @@
     expect(")");
     return [=](uint64_t Dot) { return getSectionSize(Name); };
   }
+  if (Tok == "ASSERT") {
+    expect("(");
+    Expr E = readExpr();
+    expect(",");
+    StringRef Msg = next();
+    expect(")");
+    return [=](uint64_t Dot) {
+      uint64_t V = E(Dot);
+      if (!V)
+        error(Msg);
+      return V;
+    };
+  }
 
   // Parse a symbol name or a number literal.
   uint64_t V = 0;
Index: test/ELF/linkerscript/linkerscript-assert.s
===================================================================
--- test/ELF/linkerscript/linkerscript-assert.s
+++ test/ELF/linkerscript/linkerscript-assert.s
@@ -0,0 +1,27 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t1.o
+
+# RUN: echo "SECTIONS {     \
+# RUN:   ASSERT(1, \"true\") \
+# RUN:  }" > %t1.script
+# RUN: ld.lld -shared -o %t1 --script %t1.script %t1.o
+# RUN: llvm-readobj %t1 > /dev/null
+
+# RUN: echo "SECTIONS {                                  \
+# RUN:   ASSERT(ASSERT(42, \"true\") == 42, \"true\") \
+# RUN:  }" > %t2.script
+# RUN: ld.lld -shared -o %t2 --script %t2.script %t1.o
+# RUN: llvm-readobj %t2 > /dev/null
+
+# RUN: echo "SECTIONS {     \
+# RUN:   ASSERT(0,\ "fail\") \
+# RUN:  }" > %t3.script
+# RUN: not ld.lld -shared -o %t3 --script %t3.script %t1.o > %t.log 2>&1
+# RUN: FileCheck %s -check-prefix=FAIL < %t.log
+# FAIL: fail
+
+# RUN: echo "SECTIONS {     \
+# RUN:   . = ASSERT(0x1000, \"true\"); \
+# RUN:  }" > %t4.script
+# RUN: ld.lld -shared -o %t4 --script %t4.script %t1.o
+# RUN: llvm-readobj %t4 > /dev/null