From 6d7c89cb40e3a36f99c82400084aa59df27f6573 Mon Sep 17 00:00:00 2001
From: mlugg <mlugg@mlugg.co.uk>
Date: Sat, 10 May 2025 11:34:19 +0100
Subject: [PATCH] build.zig: use correct module graph for compiler unit tests

---
 build.zig | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/build.zig b/build.zig
index 00c1254f38..ecc807616a 100644
--- a/build.zig
+++ b/build.zig
@@ -508,11 +508,9 @@ pub fn build(b: *std.Build) !void {
     test_step.dependOn(unit_tests_step);
 
     const unit_tests = b.addTest(.{
-        .root_module = b.createModule(.{
-            .root_source_file = b.path("src/main.zig"),
+        .root_module = addCompilerMod(b, .{
             .optimize = optimize,
             .target = target,
-            .link_libc = link_libc,
             .single_threaded = single_threaded,
         }),
         .filters = test_filters,
@@ -520,6 +518,9 @@ pub fn build(b: *std.Build) !void {
         .use_lld = use_llvm,
         .zig_lib_dir = b.path("lib"),
     });
+    if (link_libc) {
+        unit_tests.root_module.link_libc = true;
+    }
     unit_tests.root_module.addOptions("build_options", exe_options);
     unit_tests_step.dependOn(&b.addRunArtifact(unit_tests).step);
 
@@ -650,7 +651,7 @@ fn addWasiUpdateStep(b: *std.Build, version: [:0]const u8) !void {
     update_zig1_step.dependOn(&copy_zig_h.step);
 }
 
-const AddCompilerStepOptions = struct {
+const AddCompilerModOptions = struct {
     optimize: std.builtin.OptimizeMode,
     target: std.Build.ResolvedTarget,
     strip: ?bool = null,
@@ -659,7 +660,7 @@ const AddCompilerStepOptions = struct {
     single_threaded: ?bool = null,
 };
 
-fn addCompilerStep(b: *std.Build, options: AddCompilerStepOptions) *std.Build.Step.Compile {
+fn addCompilerMod(b: *std.Build, options: AddCompilerModOptions) *std.Build.Module {
     const compiler_mod = b.createModule(.{
         .root_source_file = b.path("src/main.zig"),
         .target = options.target,
@@ -682,10 +683,14 @@ fn addCompilerStep(b: *std.Build, options: AddCompilerStepOptions) *std.Build.St
     compiler_mod.addImport("aro", aro_mod);
     compiler_mod.addImport("aro_translate_c", aro_translate_c_mod);
 
+    return compiler_mod;
+}
+
+fn addCompilerStep(b: *std.Build, options: AddCompilerModOptions) *std.Build.Step.Compile {
     const exe = b.addExecutable(.{
         .name = "zig",
         .max_rss = 7_800_000_000,
-        .root_module = compiler_mod,
+        .root_module = addCompilerMod(b, options),
     });
     exe.stack_size = stack_size;