diff --git a/lib/MC/WinCOFFObjectWriter.cpp b/lib/MC/WinCOFFObjectWriter.cpp
index 27dc5a12a69..8e5377980d7 100644
--- a/lib/MC/WinCOFFObjectWriter.cpp
+++ b/lib/MC/WinCOFFObjectWriter.cpp
@@ -632,8 +632,10 @@ void WinCOFFObjectWriter::ExecutePostLayoutBinding(MCAssembler &Asm,
                                                    const MCAsmLayout &Layout) {
   // "Define" each section & symbol. This creates section & symbol
   // entries in the staging area.
-
-  static_assert(sizeof(COFF::AuxiliaryFile::FileName) == COFF::SymbolSize,
+  // FIXME: this used to be
+  //   sizeof(COFF::AuxiliaryFile::FileName) == COFF::SymbolSize
+  // but VS2013 can't compile that.
+  static_assert(sizeof(COFF::AuxiliaryFile) == COFF::SymbolSize,
                 "size mismatch for COFF::AuxiliaryFile::FileName");
   for (auto FI = Asm.file_names_begin(), FE = Asm.file_names_end();
        FI != FE; ++FI) {