Avoid MSVCRT assertion on comparing phdr iterators

llvm-svn: 171591
diff --git a/lld/lib/ReaderWriter/ELF/WriterELF.cpp b/lld/lib/ReaderWriter/ELF/WriterELF.cpp
index fed76362..d410da2 100644
--- a/lld/lib/ReaderWriter/ELF/WriterELF.cpp
+++ b/lld/lib/ReaderWriter/ELF/WriterELF.cpp
@@ -1213,7 +1213,9 @@
   ELFProgramHeader()
   : Chunk<target_endianness, max_align, is64Bits>(
       "elfphdr",
-      Chunk<target_endianness, max_align, is64Bits>::K_ELFProgramHeader) { }
+      Chunk<target_endianness, max_align, is64Bits>::K_ELFProgramHeader) {
+    resetProgramHeaders();
+  }
 
   bool addSegment(Segment<target_endianness, max_align, is64Bits> *segment) {
     Elf_Phdr *phdr = nullptr;