diff --git a/lib/MC/WinCOFFObjectWriter.cpp b/lib/MC/WinCOFFObjectWriter.cpp
index e98777894a7..27dc5a12a69 100644
--- a/lib/MC/WinCOFFObjectWriter.cpp
+++ b/lib/MC/WinCOFFObjectWriter.cpp
@@ -638,7 +638,7 @@ void WinCOFFObjectWriter::ExecutePostLayoutBinding(MCAssembler &Asm,
   for (auto FI = Asm.file_names_begin(), FE = Asm.file_names_end();
        FI != FE; ++FI) {
     // round up to calculate the number of auxiliary symbols required
-    unsigned Count = (FI->size() + COFF::SymbolSize) / COFF::SymbolSize;
+    unsigned Count = (FI->size() + COFF::SymbolSize - 1) / COFF::SymbolSize;
 
     COFFSymbol *file = createSymbol(".file");
     file->Data.StorageClass = COFF::IMAGE_SYM_CLASS_FILE;
diff --git a/test/MC/COFF/file.s b/test/MC/COFF/file.s
index a258693839c..72eee90842a 100644
--- a/test/MC/COFF/file.s
+++ b/test/MC/COFF/file.s
@@ -2,16 +2,16 @@
 // RUN:   | FileCheck %s -check-prefix CHECK-PRINT
 
 	.file "null-padded.asm"
-// CHECK-PRINT: .file
+// CHECK-PRINT: (nx 1) {{0x[0-9]+}} .file
 // CHECK-PRINT-NEXT: AUX null-padded.asm{{$}}
 
 	.file "eighteen-chars.asm"
 
-// CHECK-PRINT: .file
+// CHECK-PRINT: (nx 1) {{0x[0-9]+}} .file
 // CHECK-PRINT-NEXT: AUX eighteen-chars.asm{{$}}
 
 	.file "multiple-auxiliary-entries.asm"
 
-// CHECK-PRINT: .file
+// CHECK-PRINT: (nx 2) {{0x[0-9]+}} .file
 // CHECK-PRINT-NEXT: AUX multiple-auxiliary-entries.asm{{$}}