write/coff: Set checksum for BSS section symbols (#718)

src/write/coff/object.rs

@@ -654,7 +654,11 @@ impl<'a> Object<'a> {
                         length: section.size as u32,
                         number_of_relocations: section.relocations.len() as u32,
                         number_of_linenumbers: 0,
-                        check_sum: checksum(section.data()),
+                        check_sum: if section.is_bss() {
+                            0
+                        } else {
+                            checksum(section.data())
+                        },
                         number: section_offsets[section_index].associative_section,
                         selection: section_offsets[section_index].selection,
                     });

tests/round_trip/bss.rs

@@ -13,6 +13,8 @@ fn coff_x86_64_bss() {
 
     let section = object.section_id(write::StandardSection::UninitializedData);
 
+    let _bss_section_symbol = object.section_symbol(section);
+
     let symbol = object.add_symbol(write::Symbol {
         name: b"v1".to_vec(),
         value: 0,
@@ -60,6 +62,16 @@ fn coff_x86_64_bss() {
 
     let mut symbols = object.symbols();
 
+    let section_symbol = symbols.next().unwrap();
+    println!("{:?}", section_symbol);
+    assert_eq!(section_symbol.name(), Ok(".bss"));
+    assert_eq!(section_symbol.kind(), SymbolKind::Section);
+    assert_eq!(section_symbol.section_index(), Some(bss_index));
+    assert_eq!(section_symbol.scope(), SymbolScope::Compilation);
+    assert!(!section_symbol.is_weak());
+    assert!(!section_symbol.is_undefined());
+    assert_eq!(section_symbol.address(), 0);
+
     let symbol = symbols.next().unwrap();
     println!("{:?}", symbol);
     assert_eq!(symbol.name(), Ok("v1"));