From fee7ba58b0fdb612e4ca1f521340cf4de0f51ba5 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Bennet=20Ble=C3=9Fmann?= <bb-github@t-online.de>
Date: Sat, 6 Jul 2024 16:21:20 +0200
Subject: [PATCH] fix stack alignement

- adjust align() in RawBlockTraits impl for Stack
- ensure ptr is always aligned in RawBlock::allock
---
 src/machine/stack.rs | 5 +++--
 src/raw_block.rs     | 5 +++--
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/machine/stack.rs b/src/machine/stack.rs
index 604a52be..7f35cdbc 100644
--- a/src/machine/stack.rs
+++ b/src/machine/stack.rs
@@ -15,7 +15,9 @@ impl RawBlockTraits for Stack {
 
     #[inline]
     fn align() -> usize {
-        mem::align_of::<HeapCellValue>()
+        mem::align_of::<OrFrame>()
+            .max(mem::align_of::<AndFrame>())
+            .max(mem::align_of::<HeapCellValue>())
     }
 }
 
@@ -281,7 +283,6 @@ mod tests {
     use crate::machine::mock_wam::*;
 
     #[test]
-    #[cfg_attr(miri, ignore = "blocked on stack.rs UB")]
     fn stack_tests() {
         let mut wam = MockWAM::new();
 
diff --git a/src/raw_block.rs b/src/raw_block.rs
index 2c10f494..0c27bdde 100644
--- a/src/raw_block.rs
+++ b/src/raw_block.rs
@@ -96,9 +96,10 @@ impl<T: RawBlockTraits> RawBlock<T> {
     }
 
     pub unsafe fn alloc(&self, size: usize) -> *mut u8 {
-        if self.free_space() >= size {
+        let aligned_size = size.next_multiple_of(size);
+        if self.free_space() >= aligned_size {
             let ptr = *self.ptr.get();
-            *self.ptr.get() = ptr.add(size) as *mut _;
+            *self.ptr.get() = ptr.add(aligned_size) as *mut _;
             ptr
         } else {
             ptr::null_mut()
-- 
2.54.0