remove "FIXME" from codebase

See #363. Please file issues rather than making TODO comments.

src/link/Dwarf.zig

@@ -23,8 +23,6 @@ debug_str: StringSection,
 pub const UpdateError = error{
     /// Indicates the error is already reported on `failed_codegen` in the Zcu.
     CodegenFail,
-    /// Indicates the error is already reported on `link_diags` in the Compilation.
-    LinkFailure,
     OutOfMemory,
 };
 
@@ -443,7 +441,6 @@ pub const Section = struct {
             const zo = elf_file.zigObjectPtr().?;
             const atom = zo.symbol(sec.index).atom(elf_file).?;
             if (atom.prevAtom(elf_file)) |_| {
-                // FIXME:JK trimming/shrinking has to be reworked on ZigObject/Elf level
                 atom.value += len;
             } else {
                 const shdr = &elf_file.sections.items(.shdr)[atom.output_section_index];

src/link/Elf.zig

@@ -3127,9 +3127,6 @@ pub fn sortShdrs(
             fileLookup(files, ref.file, zig_object_ptr).?.atom(ref.index).?.output_section_index = atom_list.output_section_index;
         }
         if (shdr.sh_type == elf.SHT_RELA) {
-            // FIXME:JK we should spin up .symtab potentially earlier, or set all non-dynamic RELA sections
-            // to point at symtab
-            // shdr.sh_link = backlinks[shdr.sh_link];
             shdr.sh_link = section_indexes.symtab.?;
             shdr.sh_info = backlinks[shdr.sh_info];
         }
@@ -3217,7 +3214,7 @@ fn updateSectionSizes(self: *Elf) !void {
             atom_list.dirty = false;
         }
 
-        // FIXME:JK this will hopefully not be needed once we create a link from Atom/Thunk to AtomList.
+        // This might not be needed if there was a link from Atom/Thunk to AtomList.
         for (self.thunks.items) |*th| {
             th.value += slice.items(.atom_list_2)[th.output_section_index].value;
         }
@@ -3303,7 +3300,6 @@ fn updateSectionSizes(self: *Elf) !void {
     self.updateShStrtabSize();
 }
 
-// FIXME:JK this is very much obsolete, remove!
 pub fn updateShStrtabSize(self: *Elf) void {
     if (self.section_indexes.shstrtab) |index| {
         self.sections.items(.shdr)[index].sh_size = self.shstrtab.items.len;
@@ -3914,7 +3910,6 @@ fn writeSyntheticSections(self: *Elf) !void {
     try self.writeShStrtab();
 }
 
-// FIXME:JK again, why is this needed?
 pub fn writeShStrtab(self: *Elf) !void {
     if (self.section_indexes.shstrtab) |index| {
         const shdr = self.sections.items(.shdr)[index];

src/link/Elf/AtomList.zig

@@ -58,7 +58,7 @@ pub fn allocate(list: *AtomList, elf_file: *Elf) !void {
     if (expand_section) last_atom_ref.* = list.lastAtom(elf_file).ref();
     shdr.sh_addralign = @max(shdr.sh_addralign, list.alignment.toByteUnits().?);
 
-    // FIXME:JK this currently ignores Thunks as valid chunks.
+    // This currently ignores Thunks as valid chunks.
     {
         var idx: usize = 0;
         while (idx < list.atoms.keys().len) : (idx += 1) {
@@ -78,7 +78,8 @@ pub fn allocate(list: *AtomList, elf_file: *Elf) !void {
         placement_atom.next_atom_ref = list.firstAtom(elf_file).ref();
     }
 
-    // FIXME:JK if we had a link from Atom to parent AtomList we would not need to update Atom's value or osec index
+    // If we had a link from Atom to parent AtomList we would not need to
+    // update Atom's value or osec index.
     for (list.atoms.keys()) |ref| {
         const atom_ptr = elf_file.atom(ref).?;
         atom_ptr.output_section_index = list.output_section_index;

src/link/Elf/ZigObject.zig

@@ -1937,8 +1937,8 @@ pub fn allocateAtom(self: *ZigObject, atom_ptr: *Atom, requires_padding: bool, e
     const shdr = &slice.items(.shdr)[atom_ptr.output_section_index];
     const last_atom_ref = &slice.items(.last_atom)[atom_ptr.output_section_index];
 
-    // FIXME:JK this only works if this atom is the only atom in the output section
-    // In every other case, we need to redo the prev/next links
+    // This only works if this atom is the only atom in the output section. In
+    // every other case, we need to redo the prev/next links.
     if (last_atom_ref.eql(atom_ptr.ref())) last_atom_ref.* = .{};
 
     const alloc_res = try elf_file.allocateChunk(.{