commit 01db3d49535d59c70de042c60ed524bca72e31f2 (tree)
parent 2b48ec1e720b1def48c0a89b35e8f60f3edb38be
Author: kcbanner <kcbanner@gmail.com>
Date: Fri, 5 Jun 2026 01:55:34 -0400
Coff: add support for outputing implibs
This initial implementation used the existing mingw/implib functionality, and so builds the implib completely during flush(). The intended solution for this would be to build the implib with a MappedFile, similar to the main linker output.
Added two new permutations to test/standalone/shared_library that exercise the `!use_llvm` path.
Diffstat:
2 files changed, 97 insertions(+), 5 deletions(-)
diff --git a/src/link/Coff.zig b/src/link/Coff.zig
@@ -17,6 +17,8 @@ const target_util = @import("../target.zig");
const Type = @import("../Type.zig");
const Value = @import("../Value.zig");
const Zcu = @import("../Zcu.zig");
+const ModuleDefinition = @import("../libs/mingw/def.zig").ModuleDefinition;
+const implib = @import("../libs/mingw/implib.zig");
base: link.File,
mf: MappedFile,
@@ -287,6 +289,7 @@ pub const ExportTable = struct {
pending_sort: bool = false,
pub const Entry = struct {
+ si: Symbol.Index,
name_index: u32,
name_len: u32,
export_address_table_ri: Reloc.Index,
@@ -1888,6 +1891,81 @@ pub fn updateErrorData(coff: *Coff, pt: Zcu.PerThread) !void {
};
}
+fn flushImplib(
+ coff: *Coff,
+ implib_file: []const u8,
+) !void {
+ // Emitting implibs is only valid for images
+ assert(coff.export_table.ni != .none);
+
+ const comp = coff.base.comp;
+ const gpa = comp.gpa;
+ const io = comp.io;
+
+ const image_name = std.mem.sliceTo(
+ coff.export_table.ni.slice(&coff.mf)[@sizeOf(std.coff.ExportDirectoryTable)..],
+ 0,
+ );
+ const machine_type = coff.targetLoad(&coff.headerPtr().machine);
+ const members = members: {
+ const def_arena: std.heap.ArenaAllocator = .init(gpa);
+ var def: ModuleDefinition = .{
+ .name = image_name,
+ .arena = def_arena,
+ .type = .mingw,
+ };
+ defer def.deinit();
+
+ try def.exports.ensureUnusedCapacity(
+ def.arena.allocator(),
+ coff.export_table.entries.count(),
+ );
+
+ const name_table_slice = coff.export_table.name_table_ni.slice(&coff.mf);
+ for (coff.export_table.entries.values(), 0..) |entry, ord| {
+ const name = name_table_slice[entry.name_index..][0..entry.name_len];
+ const section_number = entry.si.get(coff).section_number;
+ const import_type: std.coff.ImportType = switch (section_number.symbol(coff)) {
+ .data, .rdata => .DATA,
+ .text => .CODE,
+ else => return comp.link_diags.fail(
+ "unsupported section for export '{s}': {s}",
+ .{ name, §ion_number.header(coff).name },
+ ),
+ };
+
+ def.exports.appendAssumeCapacity(.{
+ .name = name,
+ .mangled_symbol_name = null,
+ .ext_name = null,
+ .import_name = null,
+ .export_as = null,
+ .no_name = false,
+ .ordinal = @intCast(ord),
+ .type = import_type,
+ .private = false,
+ });
+ }
+
+ def.fixupForImportLibraryGeneration(machine_type);
+ break :members try implib.getMembers(gpa, def, machine_type);
+ };
+ defer members.deinit();
+
+ const lib_sub_path = try std.fs.path.join(gpa, &.{
+ std.fs.path.dirname(coff.base.emit.sub_path) orelse "",
+ implib_file,
+ });
+ defer gpa.free(lib_sub_path);
+
+ const lib_final_file = try coff.base.emit.root_dir.handle.createFile(io, lib_sub_path, .{ .truncate = true });
+ defer lib_final_file.close(io);
+ var buffer: [1024]u8 = undefined;
+ var file_writer = lib_final_file.writer(io, &buffer);
+ try implib.writeCoffArchive(gpa, &file_writer.interface, members);
+ try file_writer.interface.flush();
+}
+
pub fn flush(
coff: *Coff,
arena: std.mem.Allocator,
@@ -1898,11 +1976,18 @@ pub fn flush(
_ = prog_node;
while (try coff.idle(tid)) {}
- // hack for stage2_x86_64 + coff
const comp = coff.base.comp;
+
+ // Implib generation should instead be done via building a MappedFile progressively
+ if (comp.emit_implib) |implib_file|
+ coff.flushImplib(implib_file) catch |err|
+ return comp.link_diags.fail("flushing implib '{s}' failed: {t}", .{ implib_file, err });
+
+ // hack for stage2_x86_64 + coff
if (comp.compiler_rt_dyn_lib) |crt_file| {
const gpa = comp.gpa;
const io = comp.io;
+
const compiler_rt_sub_path = try std.fs.path.join(gpa, &.{
std.fs.path.dirname(coff.base.emit.sub_path) orelse "",
std.fs.path.basename(crt_file.full_object_path.sub_path),
@@ -2670,6 +2755,7 @@ fn updateExportsInner(
);
gop.value_ptr.* = .{
+ .si = export_si,
.name_index = @intCast(name_index),
.name_len = @intCast(name.len),
.export_address_table_ri = @enumFromInt(coff.relocs.items.len),
@@ -2683,6 +2769,7 @@ fn updateExportsInner(
.{ .AMD64 = .ADDR32NB },
);
} else {
+ gop.value_ptr.si = export_si;
const reloc = gop.value_ptr.*.export_address_table_ri.get(coff);
reloc.target = export_si;
export_si.applyTargetRelocs(coff);
diff --git a/test/standalone/shared_library/build.zig b/test/standalone/shared_library/build.zig
@@ -7,11 +7,15 @@ pub fn build(b: *std.Build) void {
const optimize: std.builtin.OptimizeMode = .Debug;
const target = b.standardTargetOptions(.{});
- const exe_names: []const []const u8 = &.{ "test", "test-dync" };
- const lib_names: []const []const u8 = &.{ "mathtest", "mathtest-dync" };
- const lib_link_libc: []const bool = &.{ false, true };
+ const exe_names: []const []const u8 = &.{ "test", "test-dync", "test-no-llvm", "test-no-llvm-dync" };
+ const lib_names: []const []const u8 = &.{ "mathtest", "mathtest-dync", "mathtest-no-llvm", "mathtest-no-llvm-dync" };
+ const lib_link_libc: []const bool = &.{ false, true, false, true };
+ const lib_use_llvm: []const bool = &.{ true, true, false, false };
+
+ for (exe_names, lib_names, lib_link_libc, lib_use_llvm) |exe_name, lib_name, dyn_libc, use_llvm| {
+ if (target.result.os.tag == .windows and target.result.abi == .gnu and dyn_libc and !use_llvm)
+ continue; // TODO: sub-compilation of compiler_rt failed (failed to link with LLD: LibCInstallationNotAvailable)
- for (exe_names, lib_names, lib_link_libc) |exe_name, lib_name, dyn_libc| {
const lib = b.addLibrary(.{
.linkage = .dynamic,
.name = lib_name,
@@ -22,6 +26,7 @@ pub fn build(b: *std.Build) void {
.optimize = optimize,
.link_libc = dyn_libc,
}),
+ .use_llvm = use_llvm,
});
const exe = b.addExecutable(.{
