1 files changed, 12 insertions, 0 deletions
diff --git a/lld/ELF/LinkerScript.cpp b/lld/ELF/LinkerScript.cpp
index 1b240f46ae9..0febb253149 100644
--- a/lld/ELF/LinkerScript.cpp
+++ b/lld/ELF/LinkerScript.cpp
@@ -756,6 +756,10 @@ template <class ELFT> uint64_t LinkerScript<ELFT>::getSymbolValue(StringRef S) {
   return 0;
 }
 
+template <class ELFT> bool LinkerScript<ELFT>::isDefined(StringRef S) {
+  return Symtab<ELFT>::X->find(S) != nullptr;
+}
+
 // 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.
@@ -1490,6 +1494,14 @@ Expr ScriptParser::readPrimary() {
     expect(")");
     return [=](uint64_t Dot) { return getConstant(Tok); };
   }
+  if (Tok == "DEFINED") {
+    expect("(");
+    StringRef Tok = next();
+    expect(")");
+    return [=](uint64_t Dot) {
+      return ScriptBase->isDefined(Tok) ? 1 : 0;
+    };
+  }
   if (Tok == "SEGMENT_START") {
     expect("(");
     next();