zig

commit 40447b25e87ece9eee2d83d1c78c365ad7ab40f1 (tree)
parent 49a270b2038709a6a0c1f4de604696278769257b
Author: Veikka Tuominen <git@vexu.eu>
Date:   Wed, 10 Aug 2022 10:59:26 +0300

Sema: fix expansion of repeated value

Closes #12386

Diffstat:
M
src/Sema.zig
 | 
5
++++-
M
test/behavior/eval.zig
 | 
17
+++++++++++++++++

2 files changed, 21 insertions(+), 1 deletion(-)
diff --git a/src/Sema.zig b/src/Sema.zig
@@ -23990,7 +23990,10 @@ fn beginComptimePtrMutation(
                                 const array_len_including_sentinel =
                                     try sema.usizeCast(block, src, parent.ty.arrayLenIncludingSentinel());
                                 const elems = try arena.alloc(Value, array_len_including_sentinel);
-                                mem.set(Value, elems, repeated_val);
+                                if (elems.len > 0) elems[0] = repeated_val;
+                                for (elems[1..]) |*elem| {
+                                    elem.* = try repeated_val.copy(arena);
+                                }
 
                                 val_ptr.* = try Value.Tag.aggregate.create(arena, elems);
 
diff --git a/test/behavior/eval.zig b/test/behavior/eval.zig
@@ -1293,3 +1293,20 @@ test "mutate through pointer-like optional at comptime" {
         try expect(payload_ptr.*.* == 16);
     }
 }
+
+test "repeated value is correctly expanded" {
+    const S = struct { x: [4]i8 = std.mem.zeroes([4]i8) };
+    const M = struct { x: [4]S = std.mem.zeroes([4]S) };
+
+    comptime {
+        var res = M{};
+        for (.{ 1, 2, 3 }) |i| res.x[i].x[i] = i;
+
+        try expectEqual(M{ .x = .{
+            .{ .x = .{ 0, 0, 0, 0 } },
+            .{ .x = .{ 0, 1, 0, 0 } },
+            .{ .x = .{ 0, 0, 2, 0 } },
+            .{ .x = .{ 0, 0, 0, 3 } },
+        } }, res);
+    }
+}