Merge pull request #22997 from Rexicon226/align-0-reify

sema: compile error on reifying align(0) fields and pointers

3 files changed, 8 insertions, 4 deletions

diff --git a/lib/std/meta.zig b/lib/std/meta.zig
index 0cee23cfa8..65b7d60c18 100644
--- a/lib/std/meta.zig
+++ b/lib/std/meta.zig
@@ -939,7 +939,7 @@ fn CreateUniqueTuple(comptime N: comptime_int, comptime types: [N]type) type {
             .type = T,
             .default_value_ptr = null,
             .is_comptime = false,
-            .alignment = 0,
+            .alignment = @alignOf(T),
         };
     }
 
diff --git a/lib/std/zig/AstGen.zig b/lib/std/zig/AstGen.zig
index 52fc41a2c9..ab81f343bd 100644
--- a/lib/std/zig/AstGen.zig
+++ b/lib/std/zig/AstGen.zig
@@ -5386,6 +5386,9 @@ fn unionDeclInner(
             return astgen.failNode(member_node, "union field missing type", .{});
         }
         if (member.ast.align_expr.unwrap()) |align_expr| {
+            if (layout == .@"packed") {
+                return astgen.failNode(align_expr, "unable to override alignment of packed union fields", .{});
+            }
             const align_inst = try expr(&block_scope, &block_scope.base, coerced_align_ri, align_expr);
             wip_members.appendToField(@intFromEnum(align_inst));
             any_aligned_fields = true;
diff --git a/lib/std/zig/llvm/Builder.zig b/lib/std/zig/llvm/Builder.zig
index f3ff63ec33..ba6faaec2c 100644
--- a/lib/std/zig/llvm/Builder.zig
+++ b/lib/std/zig/llvm/Builder.zig
@@ -8533,18 +8533,19 @@ pub const Metadata = enum(u32) {
                     .type = []const u8,
                     .default_value_ptr = null,
                     .is_comptime = false,
-                    .alignment = 0,
+                    .alignment = @alignOf([]const u8),
                 };
             }
             fmt_str = fmt_str ++ "(";
             inline for (fields[2..], names) |*field, name| {
                 fmt_str = fmt_str ++ "{[" ++ name ++ "]f}";
+                const T = std.fmt.Formatter(FormatData, format);
                 field.* = .{
                     .name = name,
-                    .type = std.fmt.Formatter(FormatData, format),
+                    .type = T,
                     .default_value_ptr = null,
                     .is_comptime = false,
-                    .alignment = 0,
+                    .alignment = @alignOf(T),
                 };
             }
             fmt_str = fmt_str ++ ")\n";