Make the -b binary .data section rw.

This matches what bfd and gold do. It also matches the common flags of
other .data sections.

llvm-svn: 291674

lld/ELF/InputFiles.cpp

@@ -857,8 +857,8 @@ template <class ELFT> void BinaryFile::parse() {
   StringRef EndName = Saver.save(Twine(Filename) + "_end");
   StringRef SizeName = Saver.save(Twine(Filename) + "_size");
 
-  auto *Section =
-      make<InputSection<ELFT>>(SHF_ALLOC, SHT_PROGBITS, 8, Data, ".data");
+  auto *Section = make<InputSection<ELFT>>(SHF_ALLOC | SHF_WRITE, SHT_PROGBITS,
+                                           8, Data, ".data");
   Sections.push_back(Section);
 
   elf::Symtab<ELFT>::X->addRegular(StartName, STV_DEFAULT, STT_OBJECT, 0, 0,

lld/test/ELF/format-binary.test

@@ -15,6 +15,7 @@
 # CHECK-NEXT:     Type: SHT_PROGBITS
 # CHECK-NEXT:     Flags [
 # CHECK-NEXT:       SHF_ALLOC
+# CHECK-NEXT:       SHF_WRITE
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
 # CHECK-NEXT:     Offset: