rust/0001-wasi-round-up-the-size-for-aligned_alloc.patch
Josh Stone fbe7f8404b Switch to unbundled wasi-libc on Fedora
Also, use emmalloc instead of CC0 dlmalloc when bundling wasi-libc.
2023-09-29 14:56:44 -07:00

34 lines
1.4 KiB
Diff

From 1c6d867d78475fd8c6274e2b64ebb27735b6cabf Mon Sep 17 00:00:00 2001
From: Josh Stone <jistone@redhat.com>
Date: Sat, 26 Aug 2023 11:50:16 -0700
Subject: [PATCH] wasi: round up the size for `aligned_alloc`
C11 `aligned_alloc` requires that the size be a multiple of the
alignment. This is enforced in the wasi-libc emmalloc implementation,
which always returns NULL if the size is not a multiple.
(The default `MALLOC_IMPL=dlmalloc` does not currently check this.)
---
library/std/src/sys/unix/alloc.rs | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/library/std/src/sys/unix/alloc.rs b/library/std/src/sys/unix/alloc.rs
index 8604b53983d6..af0089978ecb 100644
--- a/library/std/src/sys/unix/alloc.rs
+++ b/library/std/src/sys/unix/alloc.rs
@@ -86,7 +86,11 @@ unsafe fn aligned_malloc(layout: &Layout) -> *mut u8 {
} else if #[cfg(target_os = "wasi")] {
#[inline]
unsafe fn aligned_malloc(layout: &Layout) -> *mut u8 {
- libc::aligned_alloc(layout.align(), layout.size()) as *mut u8
+ // C11 aligned_alloc requires that the size be a multiple of the alignment.
+ // Layout already checks that the size rounded up doesn't overflow isize::MAX.
+ let align = layout.align();
+ let size = layout.size().next_multiple_of(align);
+ libc::aligned_alloc(align, size) as *mut u8
}
} else {
#[inline]
--
2.41.0