Auto merge of #972 - gnzlbg:packed, r=alexcrichton
Fix undefined-behavior on MacOSX structs in stdbuilds
Some MacOSX structs have an incorrect layout that results in undefined behavior. This is because on `x86_64` the MacOSX kernel headers define these using `#pragma pack 4`.
This PR fixes their layout using `repr(packed(4))` . Since it is only available on nightly, it is only enabled for stdbuilds .
diff --git a/.travis.yml b/.travis.yml
index 6acf0a8..dc2cdab 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -22,9 +22,9 @@
secure: "e2/3QjgRN9atOuSHp22TrYG7QVKcYUWY48Hi9b60w+r1+BhPkTseIJLte7WefRhdXtqpjjUJTooKDhnurFOeHaCT+nmBgiv+FPU893sBl4bhesY4m0vgUJVbNZcs6lTImYekWVb+aqjGdgV/XAgCw7c3kPmrZV0MzGDWL64Xaps="
matrix:
include:
- # 1.0.0 compat
+ # 1.13.0 compat
- env: TARGET=x86_64-unknown-linux-gnu NO_ADD=1
- rust: 1.0.0
+ rust: 1.13.0
script: rm -f Cargo.lock && cargo build
install:
diff --git a/libc-test/build.rs b/libc-test/build.rs
index 0f4efdc..74a0b4b 100644
--- a/libc-test/build.rs
+++ b/libc-test/build.rs
@@ -416,7 +416,9 @@
// which is absent in glibc, has to be defined.
"__timeval" if linux => true,
- // The alignment of this is 4 on 64-bit OSX...
+ // Fixed on stdbuild with repr(packed(4))
+ // Once repr_packed stabilizes we can fix this unconditionally
+ // and remove this check.
"kevent" | "shmid_ds" if apple && x86_64 => true,
// This is actually a union, not a struct
diff --git a/src/lib.rs b/src/lib.rs
index 2555480..877e87d 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -87,7 +87,7 @@
// Attributes needed when building as part of the standard library
#![cfg_attr(feature = "stdbuild", feature(no_std, staged_api, custom_attribute, cfg_target_vendor))]
-#![cfg_attr(feature = "stdbuild", feature(link_cfg))]
+#![cfg_attr(feature = "stdbuild", feature(link_cfg, repr_packed))]
#![cfg_attr(feature = "stdbuild", no_std)]
#![cfg_attr(feature = "stdbuild", staged_api)]
#![cfg_attr(feature = "stdbuild", allow(warnings))]
diff --git a/src/unix/bsd/apple/mod.rs b/src/unix/bsd/apple/mod.rs
index 9cd5db6..8fb1a12 100644
--- a/src/unix/bsd/apple/mod.rs
+++ b/src/unix/bsd/apple/mod.rs
@@ -245,7 +245,7 @@
pub f_reserved: [::uint32_t; 8],
}
- // FIXME: this should have align 4 but it's got align 8 on 64-bit
+ #[cfg_attr(feature = "stdbuild", repr(packed(4)))]
pub struct kevent {
pub ident: ::uintptr_t,
pub filter: ::int16_t,
@@ -524,7 +524,7 @@
pub _key: ::key_t,
}
- // FIXME: this should have align 4 but it's got align 8 on 64-bit
+ #[cfg_attr(feature = "stdbuild", repr(packed(4)))]
pub struct shmid_ds {
pub shm_perm: ipc_perm,
pub shm_segsz: ::size_t,