From aa0fbbcb3917ac988757263e064540e1be3402eb Mon Sep 17 00:00:00 2001
From: Jakub Konka <kubkon@jakubkonka.com>
Date: Sat, 11 Nov 2023 07:31:40 +0100
Subject: elf: check for empty relocs buffers in ZigObject before emitting
 section

---
 src/link/Elf.zig           | 7 +++++--
 src/link/Elf/ZigObject.zig | 5 ++++-
 2 files changed, 9 insertions(+), 3 deletions(-)

(limited to 'src')

diff --git a/src/link/Elf.zig b/src/link/Elf.zig
index 90aff333db..3ddea985e0 100644
--- a/src/link/Elf.zig
+++ b/src/link/Elf.zig
@@ -4783,7 +4783,6 @@ fn writeAtomsObject(self: *Elf) !void {
             const atom_ptr = self.atom(atom_index).?;
             assert(atom_ptr.flags.alive);
 
-            const object = atom_ptr.file(self).?.object;
             const offset = math.cast(usize, atom_ptr.value - shdr.sh_addr - base_offset) orelse
                 return error.Overflow;
             const size = math.cast(usize, atom_ptr.size) orelse return error.Overflow;
@@ -4796,7 +4795,11 @@ fn writeAtomsObject(self: *Elf) !void {
 
             // TODO decompress directly into provided buffer
             const out_code = buffer[offset..][0..size];
-            const in_code = try object.codeDecompressAlloc(self, atom_index);
+            const in_code = switch (atom_ptr.file(self).?) {
+                .object => |x| try x.codeDecompressAlloc(self, atom_index),
+                .zig_object => |x| try x.codeAlloc(self, atom_index),
+                else => unreachable,
+            };
             defer gpa.free(in_code);
             @memcpy(out_code, in_code);
         }
diff --git a/src/link/Elf/ZigObject.zig b/src/link/Elf/ZigObject.zig
index d7f7bbc174..ed286be261 100644
--- a/src/link/Elf/ZigObject.zig
+++ b/src/link/Elf/ZigObject.zig
@@ -286,6 +286,7 @@ pub fn addAtom(self: *ZigObject, elf_file: *Elf) !Symbol.Index {
     self.local_esyms.items(.elf_sym)[esym_index].st_shndx = SHN_ATOM;
     symbol_ptr.esym_index = esym_index;
 
+    // TODO I'm thinking that maybe we shouldn' set this value unless it's actually needed?
     const relocs_index = @as(u32, @intCast(self.relocs.items.len));
     const relocs = try self.relocs.addOne(gpa);
     relocs.* = .{};
@@ -490,7 +491,9 @@ pub fn addAtomsToRelaSections(self: ZigObject, elf_file: *Elf) !void {
     for (self.atoms.items) |atom_index| {
         const atom = elf_file.atom(atom_index) orelse continue;
         if (!atom.flags.alive) continue;
-        _ = atom.relocsShndx() orelse continue;
+        const rela_shndx = atom.relocsShndx() orelse continue;
+        // TODO this check will become obsolete when we rework our relocs mechanism at the ZigObject level
+        if (self.relocs.items[rela_shndx].items.len == 0) continue;
         const out_shndx = atom.outputShndx().?;
         const out_shdr = elf_file.shdrs.items[out_shndx];
         if (out_shdr.sh_type == elf.SHT_NOBITS) continue;
-- 
cgit v1.2.3