[lto] Provide a file name for the combined LTO object.

Otherwise, we get diagnostics like:

    undefined symbol: foo in

Which isn't particularly useful.

llvm-svn: 264089

diff --git a/lld/ELF/SymbolTable.cpp b/lld/ELF/SymbolTable.cpp
index a30e352..0c042ed 100644 (file)
--- a/lld/ELF/SymbolTable.cpp
+++ b/lld/ELF/SymbolTable.cpp
@@ -168,7 +168,8 @@ std::unique_ptr<InputFile> SymbolTable<ELFT>::codegen(Module &M) {
                               TargetMachine::CGFT_ObjectFile))
     fatal("failed to setup codegen");
   CodeGenPasses.run(M);
-  LtoBuffer = MemoryBuffer::getMemBuffer(OwningLTOData, "", false);
+  LtoBuffer = MemoryBuffer::getMemBuffer(
+      OwningLTOData, "LLD-INTERNAL-combined-lto-object", false);
   if (Config->SaveTemps)
     saveLtoObjectFile(LtoBuffer->getBuffer());
   return createObjectFile(*LtoBuffer);

diff --git a/lld/test/ELF/lto/combined-lto-object-name.ll b/lld/test/ELF/lto/combined-lto-object-name.ll
new file mode 100644 (file)
index 0000000..fe4e021
--- /dev/null
+++ b/lld/test/ELF/lto/combined-lto-object-name.ll
@@ -0,0 +1,14 @@
+; REQUIRES: x86
+; RUN: llvm-as %s -o %t.o
+; RUN: not ld.lld -m elf_x86_64 %t.o -o %t2 2>&1 | FileCheck %s
+
+target triple = "x86_64-unknown-linux-gnu"
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+
+declare void @foo()
+define void @_start() {
+  call void @foo()
+  ret void
+}
+
+; CHECK: undefined symbol: foo in LLD-INTERNAL-combined-lto-object