diff --git a/llvm/lib/ObjectYAML/COFFYAML.cpp b/llvm/lib/ObjectYAML/COFFYAML.cpp
index 5a85e22e4f49..6e5cdce89060 100644
--- a/llvm/lib/ObjectYAML/COFFYAML.cpp
+++ b/llvm/lib/ObjectYAML/COFFYAML.cpp
@@ -448,24 +448,24 @@ void MappingTraits<COFFYAML::PEHeader>::mapping(IO &IO,
   MappingNormalization<NDLLCharacteristics, uint16_t> NDC(
       IO, PH.Header.DLLCharacteristics);
 
-  IO.mapRequired("AddressOfEntryPoint", PH.Header.AddressOfEntryPoint);
-  IO.mapRequired("ImageBase", PH.Header.ImageBase);
-  IO.mapRequired("SectionAlignment", PH.Header.SectionAlignment);
-  IO.mapRequired("FileAlignment", PH.Header.FileAlignment);
-  IO.mapRequired("MajorOperatingSystemVersion",
+  IO.mapOptional("AddressOfEntryPoint", PH.Header.AddressOfEntryPoint);
+  IO.mapOptional("ImageBase", PH.Header.ImageBase);
+  IO.mapOptional("SectionAlignment", PH.Header.SectionAlignment, 1);
+  IO.mapOptional("FileAlignment", PH.Header.FileAlignment, 1);
+  IO.mapOptional("MajorOperatingSystemVersion",
                  PH.Header.MajorOperatingSystemVersion);
-  IO.mapRequired("MinorOperatingSystemVersion",
+  IO.mapOptional("MinorOperatingSystemVersion",
                  PH.Header.MinorOperatingSystemVersion);
-  IO.mapRequired("MajorImageVersion", PH.Header.MajorImageVersion);
-  IO.mapRequired("MinorImageVersion", PH.Header.MinorImageVersion);
-  IO.mapRequired("MajorSubsystemVersion", PH.Header.MajorSubsystemVersion);
-  IO.mapRequired("MinorSubsystemVersion", PH.Header.MinorSubsystemVersion);
-  IO.mapRequired("Subsystem", NWS->Subsystem);
-  IO.mapRequired("DLLCharacteristics", NDC->Characteristics);
-  IO.mapRequired("SizeOfStackReserve", PH.Header.SizeOfStackReserve);
-  IO.mapRequired("SizeOfStackCommit", PH.Header.SizeOfStackCommit);
-  IO.mapRequired("SizeOfHeapReserve", PH.Header.SizeOfHeapReserve);
-  IO.mapRequired("SizeOfHeapCommit", PH.Header.SizeOfHeapCommit);
+  IO.mapOptional("MajorImageVersion", PH.Header.MajorImageVersion);
+  IO.mapOptional("MinorImageVersion", PH.Header.MinorImageVersion);
+  IO.mapOptional("MajorSubsystemVersion", PH.Header.MajorSubsystemVersion);
+  IO.mapOptional("MinorSubsystemVersion", PH.Header.MinorSubsystemVersion);
+  IO.mapOptional("Subsystem", NWS->Subsystem);
+  IO.mapOptional("DLLCharacteristics", NDC->Characteristics);
+  IO.mapOptional("SizeOfStackReserve", PH.Header.SizeOfStackReserve);
+  IO.mapOptional("SizeOfStackCommit", PH.Header.SizeOfStackCommit);
+  IO.mapOptional("SizeOfHeapReserve", PH.Header.SizeOfHeapReserve);
+  IO.mapOptional("SizeOfHeapCommit", PH.Header.SizeOfHeapCommit);
 
   IO.mapOptional("NumberOfRvaAndSize", PH.Header.NumberOfRvaAndSize,
                  COFF::NUM_DATA_DIRECTORIES + 1);