changes from feedback

README.md

@@ -227,7 +227,7 @@ degree documented below):
 - We have unofficial support (not maintained by the Miri team itself) for some further operating systems.
   - `freebsd`: **maintainer wanted**. Supports `std::env` and parts of `std::{thread, fs}`, but not `std::sync`.
   - `android`: **maintainer wanted**. Support very incomplete, but a basic "hello world" works.
-  - `solaris/illumos`: @devnexen. Support very incomplete, but a basic "hello world" works.
+  - `solaris/illumos`: maintained by @devnexen. Support very incomplete, but a basic "hello world" works.
   - `wasm`: **maintainer wanted**. Support very incomplete, not even standard output works, but an empty `main` function works.
 - For targets on other operating systems, Miri might fail before even reaching the `main` function.
 

ci/ci.sh

@@ -146,7 +146,7 @@ case $HOST_TARGET in
     MIRI_TEST_TARGET=x86_64-unknown-freebsd run_tests_minimal $BASIC panic/panic concurrency/simple atomic threadname libc-getentropy libc-getrandom libc-misc fs env num_cpus
     MIRI_TEST_TARGET=i686-unknown-freebsd   run_tests_minimal $BASIC panic/panic concurrency/simple atomic threadname libc-getentropy libc-getrandom libc-misc fs env num_cpus
     MIRI_TEST_TARGET=aarch64-linux-android  run_tests_minimal $VERY_BASIC hello panic/panic
-    MIRI_TEST_TARGET=x86_64-unknown-illumos run_tests_minimal $VERY_BASIC hello panic/panic
+    MIRI_TEST_TARGET=x86_64-unknown-illumos run_tests_minimal $VERY_BASIC hello panic/panic pthread-sync
     MIRI_TEST_TARGET=wasm32-wasi run_tests_minimal $VERY_BASIC wasm
     MIRI_TEST_TARGET=wasm32-unknown-unknown run_tests_minimal $VERY_BASIC wasm
     MIRI_TEST_TARGET=thumbv7em-none-eabihf run_tests_minimal no_std

src/shims/unix/sync.rs

@@ -68,11 +68,20 @@ fn mutexattr_set_kind<'mir, 'tcx: 'mir>(
 // (the kind has to be at this particular offset for compatibility with Linux's static initializer
 // macros, e.g. PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP.)
 
+#[inline]
+fn mutex_id_offset<'mir, 'tcx: 'mir>(ecx: &MiriInterpCx<'mir, 'tcx>) -> u64 {
+    if matches!(&*ecx.tcx.sess.target.os, "macos") { 4 } else { 0 }
+}
+
 fn mutex_get_id<'mir, 'tcx: 'mir>(
     ecx: &mut MiriInterpCx<'mir, 'tcx>,
     mutex_op: &OpTy<'tcx, Provenance>,
 ) -> InterpResult<'tcx, MutexId> {
-    ecx.mutex_get_or_create_id(mutex_op, ecx.libc_ty_layout("pthread_mutex_t"), 4)
+    ecx.mutex_get_or_create_id(
+        mutex_op,
+        ecx.libc_ty_layout("pthread_mutex_t"),
+        mutex_id_offset(ecx),
+    )
 }
 
 fn mutex_reset_id<'mir, 'tcx: 'mir>(
@@ -81,7 +90,7 @@ fn mutex_reset_id<'mir, 'tcx: 'mir>(
 ) -> InterpResult<'tcx, ()> {
     ecx.deref_pointer_and_write(
         mutex_op,
-        4,
+        mutex_id_offset(ecx),
         Scalar::from_i32(0),
         ecx.libc_ty_layout("pthread_mutex_t"),
         ecx.machine.layouts.u32,