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MachO: emit absolute path in N_OSO stabs #25529

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Merged
merged 1 commit into from
Oct 10, 2025
Merged

MachO: emit absolute path in N_OSO stabs #25529

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16 changes: 11 additions & 5 deletions src/link/MachO.zig
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Original file line number Diff line number Diff line change
Expand Up @@ -919,7 +919,16 @@ fn addObject(self: *MachO, path: Path, handle: File.HandleIndex, offset: u64) !v
const tracy = trace(@src());
defer tracy.end();

const gpa = self.base.comp.gpa;
const comp = self.base.comp;
const gpa = comp.gpa;

const abs_path = try std.fs.path.resolvePosix(gpa, &.{
comp.dirs.cwd,
path.root_dir.path orelse ".",
path.sub_path,
});
errdefer gpa.free(abs_path);

const mtime: u64 = mtime: {
const file = self.getFileHandle(handle);
const stat = file.stat() catch break :mtime 0;
Expand All @@ -928,10 +937,7 @@ fn addObject(self: *MachO, path: Path, handle: File.HandleIndex, offset: u64) !v
const index = @as(File.Index, @intCast(try self.files.addOne(gpa)));
self.files.set(index, .{ .object = .{
.offset = offset,
.path = .{
.root_dir = path.root_dir,
.sub_path = try gpa.dupe(u8, path.sub_path),
},
.path = abs_path,
.file_handle = handle,
.mtime = mtime,
.index = index,
Expand Down
24 changes: 16 additions & 8 deletions src/link/MachO/Archive.zig
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Original file line number Diff line number Diff line change
Expand Up @@ -5,8 +5,9 @@ pub fn deinit(self: *Archive, allocator: Allocator) void {
}

pub fn unpack(self: *Archive, macho_file: *MachO, path: Path, handle_index: File.HandleIndex, fat_arch: ?fat.Arch) !void {
const gpa = macho_file.base.comp.gpa;
const diags = &macho_file.base.comp.link_diags;
const comp = macho_file.base.comp;
const gpa = comp.gpa;
const diags = &comp.link_diags;

var arena = std.heap.ArenaAllocator.init(gpa);
defer arena.deinit();
Expand Down Expand Up @@ -55,23 +56,30 @@ pub fn unpack(self: *Archive, macho_file: *MachO, path: Path, handle_index: File
mem.eql(u8, name, SYMDEF_SORTED) or
mem.eql(u8, name, SYMDEF64_SORTED)) continue;

const abs_path = try std.fs.path.resolvePosix(gpa, &.{
comp.dirs.cwd,
path.root_dir.path orelse ".",
path.sub_path,
});
errdefer gpa.free(abs_path);

const o_basename = try gpa.dupe(u8, name);
errdefer gpa.free(o_basename);

const object: Object = .{
.offset = pos,
.in_archive = .{
.path = .{
.root_dir = path.root_dir,
.sub_path = try gpa.dupe(u8, path.sub_path),
},
.path = abs_path,
.size = hdr_size,
},
.path = Path.initCwd(try gpa.dupe(u8, name)),
.path = o_basename,
.file_handle = handle_index,
.index = undefined,
.alive = false,
.mtime = hdr.date() catch 0,
};

log.debug("extracting object '{f}' from archive '{f}'", .{ object.path, path });
log.debug("extracting object '{s}' from archive '{f}'", .{ o_basename, path });

try self.objects.append(gpa, object);
}
Expand Down
81 changes: 30 additions & 51 deletions src/link/MachO/Object.zig
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Original file line number Diff line number Diff line change
@@ -1,8 +1,9 @@
/// Non-zero for fat object files or archives
offset: u64,
/// Archive files cannot contain subdirectories, so only the basename is needed
/// for output. However, the full path is kept for error reporting.
path: Path,
/// If `in_archive` is not `null`, this is the basename of the object in the archive. Otherwise,
/// this is a fully-resolved absolute path, because that is the path we need to embed in stabs to
/// ensure the output does not depend on its cwd.
path: []u8,
file_handle: File.HandleIndex,
mtime: u64,
index: File.Index,
Expand Down Expand Up @@ -41,8 +42,8 @@ output_symtab_ctx: MachO.SymtabCtx = .{},
output_ar_state: Archive.ArState = .{},

pub fn deinit(self: *Object, allocator: Allocator) void {
if (self.in_archive) |*ar| allocator.free(ar.path.sub_path);
allocator.free(self.path.sub_path);
if (self.in_archive) |*ar| allocator.free(ar.path);
allocator.free(self.path);
for (self.sections.items(.relocs), self.sections.items(.subsections)) |*relocs, *sub| {
relocs.deinit(allocator);
sub.deinit(allocator);
Expand Down Expand Up @@ -1703,7 +1704,7 @@ pub fn updateArSize(self: *Object, macho_file: *MachO) !void {
pub fn writeAr(self: Object, ar_format: Archive.Format, macho_file: *MachO, writer: anytype) !void {
// Header
const size = try macho_file.cast(usize, self.output_ar_state.size);
const basename = std.fs.path.basename(self.path.sub_path);
const basename = std.fs.path.basename(self.path);
try Archive.writeHeader(basename, size, ar_format, writer);
// Data
const file = macho_file.getFileHandle(self.file_handle);
Expand Down Expand Up @@ -1756,12 +1757,7 @@ pub fn calcSymtabSize(self: *Object, macho_file: *MachO) void {
self.calcStabsSize(macho_file);
}

fn pathLen(path: Path) usize {
// +1 for the path separator
return (if (path.root_dir.path) |p| p.len + @intFromBool(path.sub_path.len != 0) else 0) + path.sub_path.len;
}

pub fn calcStabsSize(self: *Object, macho_file: *MachO) void {
fn calcStabsSize(self: *Object, macho_file: *MachO) void {
if (self.compile_unit) |cu| {
const comp_dir = cu.getCompDir(self.*);
const tu_name = cu.getTuName(self.*);
Expand All @@ -1771,9 +1767,11 @@ pub fn calcStabsSize(self: *Object, macho_file: *MachO) void {
self.output_symtab_ctx.strsize += @as(u32, @intCast(tu_name.len + 1)); // tu_name

if (self.in_archive) |ar| {
self.output_symtab_ctx.strsize += @intCast(pathLen(ar.path) + 1 + self.path.basename().len + 1 + 1);
// "/path/to/archive.a(object.o)\x00"
self.output_symtab_ctx.strsize += @intCast(ar.path.len + self.path.len + 3);
} else {
self.output_symtab_ctx.strsize += @intCast(pathLen(self.path) + 1);
// "/path/to/object.o\x00"
self.output_symtab_ctx.strsize += @intCast(self.path.len + 1);
}

for (self.symbols.items, 0..) |sym, i| {
Expand Down Expand Up @@ -2018,7 +2016,7 @@ pub fn writeSymtab(self: Object, macho_file: *MachO, ctx: anytype) void {
self.writeStabs(n_strx, macho_file, ctx);
}

pub fn writeStabs(self: Object, stroff: u32, macho_file: *MachO, ctx: anytype) void {
fn writeStabs(self: Object, stroff: u32, macho_file: *MachO, ctx: anytype) void {
const writeFuncStab = struct {
inline fn writeFuncStab(
n_strx: u32,
Expand Down Expand Up @@ -2103,38 +2101,20 @@ pub fn writeStabs(self: Object, stroff: u32, macho_file: *MachO, ctx: anytype) v
};
index += 1;
if (self.in_archive) |ar| {
if (ar.path.root_dir.path) |p| {
@memcpy(ctx.strtab.items[n_strx..][0..p.len], p);
n_strx += @intCast(p.len);
if (ar.path.sub_path.len != 0) {
ctx.strtab.items[n_strx] = '/';
n_strx += 1;
}
}
@memcpy(ctx.strtab.items[n_strx..][0..ar.path.sub_path.len], ar.path.sub_path);
n_strx += @intCast(ar.path.sub_path.len);
ctx.strtab.items[n_strx] = '(';
n_strx += 1;
const basename = self.path.basename();
@memcpy(ctx.strtab.items[n_strx..][0..basename.len], basename);
n_strx += @intCast(basename.len);
ctx.strtab.items[n_strx] = ')';
n_strx += 1;
ctx.strtab.items[n_strx] = 0;
// "/path/to/archive.a(object.o)\x00"
@memcpy(ctx.strtab.items[n_strx..][0..ar.path.len], ar.path);
n_strx += @intCast(ar.path.len);
ctx.strtab.items[n_strx..][0] = '(';
n_strx += 1;
@memcpy(ctx.strtab.items[n_strx..][0..self.path.len], self.path);
n_strx += @intCast(self.path.len);
ctx.strtab.items[n_strx..][0..2].* = ")\x00".*;
n_strx += 2;
} else {
if (self.path.root_dir.path) |p| {
@memcpy(ctx.strtab.items[n_strx..][0..p.len], p);
n_strx += @intCast(p.len);
if (self.path.sub_path.len != 0) {
ctx.strtab.items[n_strx] = '/';
n_strx += 1;
}
}
@memcpy(ctx.strtab.items[n_strx..][0..self.path.sub_path.len], self.path.sub_path);
n_strx += @intCast(self.path.sub_path.len);
ctx.strtab.items[n_strx] = 0;
n_strx += 1;
// "/path/to/object.o\x00"
@memcpy(ctx.strtab.items[n_strx..][0..self.path.len], self.path);
ctx.strtab.items[n_strx..][self.path.len] = 0;
n_strx += @intCast(self.path.len + 1);
}

for (self.symbols.items, 0..) |sym, i| {
Expand Down Expand Up @@ -2621,11 +2601,9 @@ pub fn fmtPath(self: Object) std.fmt.Alt(Object, formatPath) {

fn formatPath(object: Object, w: *Writer) Writer.Error!void {
if (object.in_archive) |ar| {
try w.print("{f}({s})", .{
ar.path, object.path.basename(),
});
try w.print("{s}({s})", .{ ar.path, object.path });
} else {
try w.print("{f}", .{object.path});
try w.writeAll(object.path);
}
}

Expand Down Expand Up @@ -2716,7 +2694,9 @@ const CompileUnit = struct {
};

const InArchive = struct {
path: Path,
/// This is a fully-resolved absolute path, because that is the path we need to embed in stabs
/// to ensure the output does not depend on its cwd.
path: []u8,
size: u32,
};

Expand Down Expand Up @@ -3094,7 +3074,6 @@ const log = std.log.scoped(.link);
const macho = std.macho;
const math = std.math;
const mem = std.mem;
const Path = std.Build.Cache.Path;
const Allocator = std.mem.Allocator;
const Writer = std.Io.Writer;

Expand Down
2 changes: 1 addition & 1 deletion src/link/MachO/relocatable.zig
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Original file line number Diff line number Diff line change
Expand Up @@ -191,7 +191,7 @@ pub fn flushStaticLib(macho_file: *MachO, comp: *Compilation, module_obj_path: ?
pos = mem.alignForward(usize, pos, 2);
state.file_off = pos;
pos += @sizeOf(Archive.ar_hdr);
pos += mem.alignForward(usize, o.path.basename().len + 1, ptr_width);
pos += mem.alignForward(usize, std.fs.path.basename(o.path).len + 1, ptr_width);
pos += try macho_file.cast(usize, state.size);
},
else => unreachable,
Expand Down