From b6b3462796fe38a071e6ed2cbcdbb5b024359f35 Mon Sep 17 00:00:00 2001
From: Veikka Tuominen <git@vexu.eu>
Date: Sun, 13 Nov 2022 20:33:13 +0200
Subject: [PATCH] std.mem.Allocator: do not return undefined pointers from
 `create`

Closes #13517
---
 lib/std/mem/Allocator.zig | 2 +-
 src/Sema.zig              | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/std/mem/Allocator.zig b/lib/std/mem/Allocator.zig
index 28ca194c29..92347c0919 100644
--- a/lib/std/mem/Allocator.zig
+++ b/lib/std/mem/Allocator.zig
@@ -167,7 +167,7 @@ pub inline fn rawFree(self: Allocator, buf: []u8, buf_align: u29, ret_addr: usiz
 /// Returns a pointer to undefined memory.
 /// Call `destroy` with the result to free the memory.
 pub fn create(self: Allocator, comptime T: type) Error!*T {
-    if (@sizeOf(T) == 0) return @as(*T, undefined);
+    if (@sizeOf(T) == 0) return @intToPtr(*T, std.math.maxInt(usize));
     const slice = try self.allocAdvancedWithRetAddr(T, null, 1, .exact, @returnAddress());
     return &slice[0];
 }
diff --git a/src/Sema.zig b/src/Sema.zig
index 493202982e..0dc53c90fa 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -18754,7 +18754,7 @@ fn zirIntToPtr(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Ai
         const addr = val.toUnsignedInt(target);
         if (!ptr_ty.isAllowzeroPtr() and addr == 0)
             return sema.fail(block, operand_src, "pointer type '{}' does not allow address zero", .{ptr_ty.fmt(sema.mod)});
-        if (addr != 0 and addr % ptr_align != 0)
+        if (addr != 0 and ptr_align != 0 and addr % ptr_align != 0)
             return sema.fail(block, operand_src, "pointer type '{}' requires aligned address", .{ptr_ty.fmt(sema.mod)});
 
         const val_payload = try sema.arena.create(Value.Payload.U64);