authorgravatar for kubkon@jakubkonka.comJakub Konka <kubkon@jakubkonka.com> 2022-08-11 00:06:31+02:00
committergravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2022-08-10 18:45:46-04:00
log45c444ff18b43d30a7277e346174ba6eca4a6193
treea1cdd6c7cfea32127fb13e1fd08b683ba37818f5
parente218b7ea0c2a907c5728006b38e7ca492e19ccb6

macho: allow unaligned offsets in object files

1 files changed, 13 insertions(+), 12 deletions(-)

src/link/MachO/Object.zig+13-12
...@@ -99,10 +99,11 @@ pub fn parse(self: *Object, allocator: Allocator, cpu_arch: std.Target.Cpu.Arch)...@@ -99,10 +99,11 @@ pub fn parse(self: *Object, allocator: Allocator, cpu_arch: std.Target.Cpu.Arch)
99 },99 },
100 .SYMTAB => {100 .SYMTAB => {
101 const symtab = cmd.cast(macho.symtab_command).?;101 const symtab = cmd.cast(macho.symtab_command).?;
102 self.in_symtab = @ptrCast(102 // Sadly, SYMTAB may be at an unaligned offset within the object file.
103 [*]const macho.nlist_64,103 self.in_symtab = @alignCast(@alignOf(macho.nlist_64), @ptrCast(
104 @alignCast(@alignOf(macho.nlist_64), &self.contents[symtab.symoff]),104 [*]align(1) const macho.nlist_64,
105 )[0..symtab.nsyms];105 self.contents.ptr + symtab.symoff,
106 ))[0..symtab.nsyms];
106 self.in_strtab = self.contents[symtab.stroff..][0..symtab.strsize];107 self.in_strtab = self.contents[symtab.stroff..][0..symtab.strsize];
107 try self.symtab.appendSlice(allocator, self.in_symtab);108 try self.symtab.appendSlice(allocator, self.in_symtab);
108 },109 },
...@@ -302,10 +303,10 @@ pub fn splitIntoAtomsOneShot(self: *Object, macho_file: *MachO, object_id: u32)...@@ -302,10 +303,10 @@ pub fn splitIntoAtomsOneShot(self: *Object, macho_file: *MachO, object_id: u32)
302 const code: ?[]const u8 = if (!sect.isZerofill()) try self.getSectionContents(sect) else null;303 const code: ?[]const u8 = if (!sect.isZerofill()) try self.getSectionContents(sect) else null;
303304
304 // Read section's list of relocations305 // Read section's list of relocations
305 const relocs = @ptrCast(306 const relocs = @alignCast(@alignOf(macho.relocation_info), @ptrCast(
306 [*]const macho.relocation_info,307 [*]align(1) const macho.relocation_info,
307 @alignCast(@alignOf(macho.relocation_info), &self.contents[sect.reloff]),308 self.contents.ptr + sect.reloff,
308 )[0..sect.nreloc];309 ))[0..sect.nreloc];
309310
310 // Symbols within this section only.311 // Symbols within this section only.
311 const filtered_syms = filterSymbolsByAddress(312 const filtered_syms = filterSymbolsByAddress(
...@@ -548,10 +549,10 @@ pub fn parseDataInCode(self: Object) ?[]const macho.data_in_code_entry {...@@ -548,10 +549,10 @@ pub fn parseDataInCode(self: Object) ?[]const macho.data_in_code_entry {
548 .DATA_IN_CODE => {549 .DATA_IN_CODE => {
549 const dice = cmd.cast(macho.linkedit_data_command).?;550 const dice = cmd.cast(macho.linkedit_data_command).?;
550 const ndice = @divExact(dice.datasize, @sizeOf(macho.data_in_code_entry));551 const ndice = @divExact(dice.datasize, @sizeOf(macho.data_in_code_entry));
551 return @ptrCast(552 return @alignCast(@alignOf(macho.data_in_code_entry), @ptrCast(
552 [*]const macho.data_in_code_entry,553 [*]align(1) const macho.data_in_code_entry,
553 @alignCast(@alignOf(macho.data_in_code_entry), &self.contents[dice.dataoff]),554 self.contents.ptr + dice.dataoff,
554 )[0..ndice];555 ))[0..ndice];
555 },556 },
556 else => {},557 else => {},
557 }558 }