diff --git a/lld/ELF/Config.h b/lld/ELF/Config.h
--- a/lld/ELF/Config.h
+++ b/lld/ELF/Config.h
@@ -90,6 +90,7 @@
   uint32_t andFeatures = 0;
   llvm::CachePruningPolicy thinLTOCachePolicy;
   llvm::StringMap<uint64_t> sectionStartMap;
+  llvm::StringRef bfdname;
   llvm::StringRef chroot;
   llvm::StringRef dynamicLinker;
   llvm::StringRef dwoDir;
diff --git a/lld/ELF/InputFiles.cpp b/lld/ELF/InputFiles.cpp
--- a/lld/ELF/InputFiles.cpp
+++ b/lld/ELF/InputFiles.cpp
@@ -138,8 +138,10 @@
       return true;
   }
 
-  if (!config->emulation.empty()) {
-    error(toString(file) + " is incompatible with " + config->emulation);
+  StringRef target =
+      !config->bfdname.empty() ? config->bfdname : config->emulation;
+  if (!target.empty()) {
+    error(toString(file) + " is incompatible with " + target);
     return false;
   }
 
@@ -148,8 +150,11 @@
     existing = objectFiles[0];
   else if (!sharedFiles.empty())
     existing = sharedFiles[0];
-  else
+  else if (!bitcodeFiles.empty())
     existing = bitcodeFiles[0];
+  else
+    llvm_unreachable("Must have -m, OUTPUT_FORMAT or existing input file to "
+                     "determine target emulation");
 
   error(toString(file) + " is incompatible with " + toString(existing));
   return false;
diff --git a/lld/ELF/ScriptParser.cpp b/lld/ELF/ScriptParser.cpp
--- a/lld/ELF/ScriptParser.cpp
+++ b/lld/ELF/ScriptParser.cpp
@@ -412,14 +412,14 @@
 void ScriptParser::readOutputFormat() {
   expect("(");
 
-  StringRef name = unquote(next());
-  StringRef s = name;
+  config->bfdname = unquote(next());
+  StringRef s = config->bfdname;
   if (s.consume_back("-freebsd"))
     config->osabi = ELFOSABI_FREEBSD;
 
   std::tie(config->ekind, config->emachine) = parseBfdName(s);
   if (config->emachine == EM_NONE)
-    setError("unknown output format name: " + name);
+    setError("unknown output format name: " + config->bfdname);
   if (s == "elf32-ntradlittlemips" || s == "elf32-ntradbigmips")
     config->mipsN32Abi = true;
 
diff --git a/lld/test/ELF/incompatible.s b/lld/test/ELF/incompatible.s
--- a/lld/test/ELF/incompatible.s
+++ b/lld/test/ELF/incompatible.s
@@ -44,6 +44,14 @@
 // RUN:   FileCheck --check-prefix=SO-AND-C-I386 %s
 // SO-AND-C-I386: c.o is incompatible with elf_i386
 
+// RUN: echo 'OUTPUT_FORMAT(elf32-i386)' > %t.script
+// RUN: not ld.lld %t.script %ta.o -o /dev/null 2>&1 | \
+// RUN:   FileCheck --check-prefix=A-AND-SCRIPT %s
+// RUN: not ld.lld %ta.o %t.script -o /dev/null 2>&1 | \
+// RUN:   FileCheck --check-prefix=A-AND-SCRIPT %s
+// RUN: not ld.lld -m elf_x86_64 %ta.o %t.script -o /dev/null 2>&1 | \
+// RUN:   FileCheck --check-prefix=A-AND-SCRIPT %s
+// A-AND-SCRIPT: a.o is incompatible with elf32-i386
 
 // We used to fail to identify this incompatibility and crash trying to
 // read a 64 bit file as a 32 bit one.