Sema: fix empty slice pointer value

We just checked that inst_child_ty was effectively a zero-bit type, so it is certainly not the non-zero alignment we are looking for. Closes ziglang#15085
jacobly0 · Mar 27, 2023 · dd24cf7 · dd24cf7
1 parent 1de64db
commit dd24cf7
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Showing 2 changed files with 13 additions and 5 deletions.
diff --git a/src/Sema.zig b/src/Sema.zig
@@ -25152,7 +25152,7 @@ fn coerceExtra(
                             .ptr = if (dest_info.@"align" != 0)
                                 try Value.Tag.int_u64.create(sema.arena, dest_info.@"align")
                             else
-                                try inst_child_ty.lazyAbiAlignment(target, sema.arena),
+                                try dest_info.pointee_type.lazyAbiAlignment(target, sema.arena),
                             .len = Value.zero,
                         });
                         return sema.addConstant(dest_ty, slice_val);

diff --git a/test/behavior/slice.zig b/test/behavior/slice.zig
@@ -723,10 +723,18 @@ test "slice with dereferenced value" {
 test "empty slice ptr is non null" {
     if (builtin.zig_backend == .stage2_aarch64 and builtin.os.tag == .macos) return error.SkipZigTest; // TODO
 
-    const empty_slice: []u8 = &[_]u8{};
-    const p: [*]u8 = empty_slice.ptr + 0;
-    const t = @ptrCast([*]i8, p);
-    try expect(@ptrToInt(t) == @ptrToInt(empty_slice.ptr));
+    {
+        const empty_slice: []u8 = &[_]u8{};
+        const p: [*]u8 = empty_slice.ptr + 0;
+        const t = @ptrCast([*]i8, p);
+        try expect(@ptrToInt(t) == @ptrToInt(empty_slice.ptr));
+    }
+    {
+        const empty_slice: []u8 = &.{};
+        const p: [*]u8 = empty_slice.ptr + 0;
+        const t = @ptrCast([*]i8, p);
+        try expect(@ptrToInt(t) == @ptrToInt(empty_slice.ptr));
+    }
 }
 
 test "slice decays to many pointer" {