[lld] [llvm] [Object][ELF] Support extended header for Object Parser in ELF (PR #162288)

[James Henderson via llvm-commits]

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@@ -889,15 +896,42 @@ Expected<uint64_t> ELFFile<ELFT>::getDynSymtabSize() const {
   return 0;
 }
 
-template <class ELFT> ELFFile<ELFT>::ELFFile(StringRef Object) : Buf(Object) {}
+template <class ELFT> ELFFile<ELFT>::ELFFile(StringRef Object) : Buf(Object) {
+  auto Header = getHeader();
+  e_phnum = Header.e_phnum;
+  e_shnum = Header.e_shnum;
+  e_shstrndx = Header.e_shstrndx;
+}
 
 template <class ELFT>
 Expected<ELFFile<ELFT>> ELFFile<ELFT>::create(StringRef Object) {
   if (sizeof(Elf_Ehdr) > Object.size())
     return createError("invalid buffer: the size (" + Twine(Object.size()) +
                        ") is smaller than an ELF header (" +
                        Twine(sizeof(Elf_Ehdr)) + ")");
-  return ELFFile(Object);
+  ELFFile Result(Object);
+
+  //
+  // sections() parse the total number of sections by considering the
+  // extended headers
+  //
+  if (Result.getHeader().HasHeaderExtension()) {
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jh7370 wrote:

Why is this done here rather than within the `ELFFile` constructor?

https://github.com/llvm/llvm-project/pull/162288