Index: test/wasm/undefined.ll
===================================================================
--- test/wasm/undefined.ll
+++ test/wasm/undefined.ll
@@ -6,10 +6,14 @@
 ; CHECK: error: {{.*}}.o: undefined symbol: foo
 ; CHECK: error: undefined symbol: baz
 
-; But succeeds if we pass a file containing 'foo' as --allow-undefined-file.
+; Succeeds if we pass a file containing 'foo' as --allow-undefined-file.
 ; RUN: echo 'foo' > %t.txt
 ; RUN: wasm-ld --check-signatures --allow-undefined-file=%t.txt -o %t.wasm %t.o
 
+; Succeeds even if a missing symbol is added via --export
+; RUN: echo 'foo' > %t.txt
+; RUN: wasm-ld --check-signatures --allow-undefined --export=xxx -o %t.wasm %t.o
+
 target triple = "wasm32-unknown-unknown-wasm"
 
 ; Takes the address of the external foo() resulting in undefined external
Index: wasm/Driver.cpp
===================================================================
--- wasm/Driver.cpp
+++ wasm/Driver.cpp
@@ -346,7 +346,7 @@
     Symbol *Sym = Symtab->find(Name);
     if (Sym && Sym->isDefined())
       Sym->setHidden(false);
-    else
+    else if (!Config->AllowUndefined)
       error("symbol exported via --export not found: " + Name);
   }