diff --git a/llvm/test/tools/llvm-size/elf-m.test b/llvm/test/tools/llvm-size/elf-m.test
--- a/llvm/test/tools/llvm-size/elf-m.test
+++ b/llvm/test/tools/llvm-size/elf-m.test
@@ -2,13 +2,11 @@
 ## specified and the input is not Mach-O.
 
 # RUN: yaml2obj %s -o %t
-# RUN: llvm-size -m %t | FileCheck %s
-# RUN: llvm-size --format=darwin %t | FileCheck %s
+# RUN: llvm-size -m %t | FileCheck -DFILE=%t %s
+# RUN: llvm-size --format=darwin %t | FileCheck -DFILE=%t %s
 
-## FIXME: The input filename should be printed but isn't currently due to
-##        https://bugs.llvm.org/show_bug.cgi?id=42971.
 # CHECK:         text    data     bss     dec     hex filename
-# CHECK-NEXT:       0       0       0       0       0
+# CHECK-NEXT:       0       0       0       0       0 [[FILE]]
 
 --- !ELF
 FileHeader:
diff --git a/llvm/tools/llvm-size/llvm-size.cpp b/llvm/tools/llvm-size/llvm-size.cpp
--- a/llvm/tools/llvm-size/llvm-size.cpp
+++ b/llvm/tools/llvm-size/llvm-size.cpp
@@ -836,6 +836,8 @@
     else if (MachO && OutputFormat == darwin && MoreThanOneFile)
       outs() << o->getFileName() << ":\n";
     printObjectSectionSizes(o);
+    if (!MachO && OutputFormat == darwin)
+      outs() << o->getFileName() << "\n";
     if (OutputFormat == berkeley) {
       if (!MachO || MoreThanOneFile)
         outs() << o->getFileName();