diff --git a/lib/std/build.zig b/lib/std/build.zig
index 6ba6a08af030f599b77ffd43c9e2d8128bcce60c..5e4f83d2789a1ed42470df5a0118a0af431e45c9 100644
--- a/lib/std/build.zig
+++ b/lib/std/build.zig
@@ -242,6 +242,20 @@ pub const Builder = struct {
         return LibExeObjStep.createObject(self, name, root_src_param);
     }
 
+    pub fn addObjectFromWriteFileStep(
+        self: *Builder,
+        name: []const u8,
+        wfs: *WriteFileStep,
+        basename: []const u8,
+    ) *LibExeObjStep {
+        return LibExeObjStep.createObject(self, name, @as(FileSource, .{
+            .write_file = .{
+                .step = wfs,
+                .basename = basename,
+            },
+        }));
+    }
+
     pub fn addSharedLibrary(self: *Builder, name: []const u8, root_src: ?[]const u8, ver: Version) *LibExeObjStep {
         const root_src_param = if (root_src) |p| @as(FileSource, .{ .path = p }) else null;
         return LibExeObjStep.createSharedLibrary(self, name, root_src_param, ver);
diff --git a/test/tests.zig b/test/tests.zig
index ae9b68c84477da8ea9904dda4e65ef83be1c22d3..7c97e46e0280d7494807eb6bafe1592372552920 100644
--- a/test/tests.zig
+++ b/test/tests.zig
@@ -737,6 +737,7 @@ pub const CompileErrorContext = struct {
         test_index: usize,
         case: *const TestCase,
         build_mode: Mode,
+        write_src: *build.WriteFileStep,
 
         const ErrLineIter = struct {
             lines: mem.SplitIterator,
@@ -756,7 +757,13 @@ pub const CompileErrorContext = struct {
             }
         };
 
-        pub fn create(context: *CompileErrorContext, name: []const u8, case: *const TestCase, build_mode: Mode) *CompileCmpOutputStep {
+        pub fn create(
+            context: *CompileErrorContext,
+            name: []const u8,
+            case: *const TestCase,
+            build_mode: Mode,
+            write_src: *build.WriteFileStep,
+        ) *CompileCmpOutputStep {
             const allocator = context.b.allocator;
             const ptr = allocator.create(CompileCmpOutputStep) catch unreachable;
             ptr.* = CompileCmpOutputStep{
@@ -766,6 +773,7 @@ pub const CompileErrorContext = struct {
                 .test_index = context.test_index,
                 .case = case,
                 .build_mode = build_mode,
+                .write_src = write_src,
             };
 
             context.test_index += 1;
@@ -776,11 +784,6 @@ pub const CompileErrorContext = struct {
             const self = @fieldParentPtr(CompileCmpOutputStep, "step", step);
             const b = self.context.b;
 
-            const root_src = fs.path.join(
-                b.allocator,
-                &[_][]const u8{ b.cache_root, self.case.sources.items[0].filename },
-            ) catch unreachable;
-
             var zig_args = ArrayList([]const u8).init(b.allocator);
             zig_args.append(b.zig_exe) catch unreachable;
 
@@ -791,7 +794,8 @@ pub const CompileErrorContext = struct {
             } else {
                 try zig_args.append("build-obj");
             }
-            zig_args.append(b.pathFromRoot(root_src)) catch unreachable;
+            const root_src_basename = self.case.sources.toSliceConst()[0].filename;
+            try zig_args.append(self.write_src.getOutputPath(root_src_basename));
 
             zig_args.append("--name") catch unreachable;
             zig_args.append("test") catch unreachable;
@@ -990,18 +994,14 @@ pub const CompileErrorContext = struct {
         if (self.test_filter) |filter| {
             if (mem.indexOf(u8, annotated_case_name, filter) == null) return;
         }
+        const write_src = b.addWriteFiles();
+        for (case.sources.toSliceConst()) |src_file| {
+            write_src.add(src_file.filename, src_file.source);
+        }
 
-        const compile_and_cmp_errors = CompileCmpOutputStep.create(self, annotated_case_name, case, .Debug);
+        const compile_and_cmp_errors = CompileCmpOutputStep.create(self, annotated_case_name, case, .Debug, write_src);
+        compile_and_cmp_errors.step.dependOn(&write_src.step);
         self.step.dependOn(&compile_and_cmp_errors.step);
-
-        for (case.sources.toSliceConst()) |src_file| {
-            const expanded_src_path = fs.path.join(
-                b.allocator,
-                &[_][]const u8{ b.cache_root, src_file.filename },
-            ) catch unreachable;
-            const write_src = b.addWriteFile(expanded_src_path, src_file.source);
-            compile_and_cmp_errors.step.dependOn(&write_src.step);
-        }
     }
 };
 
@@ -1195,10 +1195,6 @@ pub const GenHContext = struct {
 
     pub fn addCase(self: *GenHContext, case: *const TestCase) void {
         const b = self.b;
-        const root_src = fs.path.join(
-            b.allocator,
-            &[_][]const u8{ b.cache_root, case.sources.items[0].filename },
-        ) catch unreachable;
 
         const mode = builtin.Mode.Debug;
         const annotated_case_name = fmt.allocPrint(self.b.allocator, "gen-h {} ({})", .{ case.name, @tagName(mode) }) catch unreachable;
@@ -1206,18 +1202,14 @@ pub const GenHContext = struct {
             if (mem.indexOf(u8, annotated_case_name, filter) == null) return;
         }
 
-        const obj = b.addObject("test", root_src);
+        const write_src = b.addWriteFiles();
+        for (case.sources.toSliceConst()) |src_file| {
+            write_src.add(src_file.filename, src_file.source);
+        }
+
+        const obj = b.addObjectFromWriteFileStep("test", write_src, case.sources.items[0].filename);
         obj.setBuildMode(mode);
 
-        for (case.sources.toSliceConst()) |src_file| {
-            const expanded_src_path = fs.path.join(
-                b.allocator,
-                &[_][]const u8{ b.cache_root, src_file.filename },
-            ) catch unreachable;
-            const write_src = b.addWriteFile(expanded_src_path, src_file.source);
-            obj.step.dependOn(&write_src.step);
-        }
-
         const cmp_h = GenHCmpOutputStep.create(self, obj, annotated_case_name, case);
 
         self.step.dependOn(&cmp_h.step);