Re: GNU Guile 2.1.6 released (beta)

[Andy Wingo <wingo@pobox.com>]

Hi,

Picking up this topic...

On Wed 25 Jan 2017 04:35, Matt Wette <matt.wette@gmail.com> writes:

>  On Jan 18, 2017, at 6:26 PM, Andy Wingo <wingo@pobox.com> wrote:
>
>  We are pleased to announce GNU Guile release 2.1.6.
>
>  Guile 2.1.6 is the sixth pre-release in what will eventually become the
>  2.2 release series. We encourage you to test this release and provide
>  feedback to guile-devel@gnu.org.
>
> So I am trying to compile using clang. This has detected issues with atomics-internal.h. I can fix most issues with casts:
> static inline uint32_t
> scm_atomic_subtract_uint32 (uint32_t *loc, uint32_t arg)
> {
> - return atomic_fetch_sub (loc, arg);
> + return atomic_fetch_sub ((_Atomic uint32_t *)loc, arg);
> }
>
> But problems remain with scm_atomic_set_pointer and scm_atomic_ref_pointer which use void** and is apparently not defined for use with atomics.
>
> Apparently gcc does not have a problem with this use but I’m guessing the C11 standard may have an issue with it.

WDYT about this?

Andy

diff --git a/libguile/atomics-internal.h b/libguile/atomics-internal.h
index f2d17e1..da3ebd8 100644
--- a/libguile/atomics-internal.h
+++ b/libguile/atomics-internal.h
@@ -31,46 +31,56 @@
 #ifdef HAVE_STDATOMIC_H
 
 #include <stdatomic.h>
+
 static inline uint32_t
 scm_atomic_subtract_uint32 (uint32_t *loc, uint32_t arg)
 {
-  return atomic_fetch_sub (loc, arg);
+  atomic_uint_least32_t *a_loc = (atomic_uint_least32_t *) loc;
+  return atomic_fetch_sub (a_loc, arg);
 }
 static inline _Bool
 scm_atomic_compare_and_swap_uint32 (uint32_t *loc, uint32_t *expected,
                                     uint32_t desired)
 {
-  return atomic_compare_exchange_weak (loc, expected, desired);
+  atomic_uint_least32_t *a_loc = (atomic_uint_least32_t *) loc;
+  return atomic_compare_exchange_weak (a_loc, expected, desired);
 }
 static inline void
 scm_atomic_set_pointer (void **loc, void *val)
 {
-  atomic_store (loc, val);
+  atomic_uintptr_t *a_loc = (atomic_uintptr_t *) loc;
+  atomic_store (a_loc, (uintptr_t) val);
 }
 static inline void *
 scm_atomic_ref_pointer (void **loc)
 {
-  return atomic_load (loc);
+  atomic_uintptr_t *a_loc = (atomic_uintptr_t *) loc;
+  return (void *) atomic_load (a_loc);
 }
 static inline void
 scm_atomic_set_scm (SCM *loc, SCM val)
 {
-  atomic_store (loc, val);
+  atomic_uintptr_t *a_loc = (atomic_uintptr_t *) loc;
+  atomic_store (a_loc, SCM_UNPACK (val));
 }
 static inline SCM
 scm_atomic_ref_scm (SCM *loc)
 {
-  return atomic_load (loc);
+  atomic_uintptr_t *a_loc = (atomic_uintptr_t *) loc;
+  return SCM_PACK (atomic_load (a_loc));
 }
 static inline SCM
 scm_atomic_swap_scm (SCM *loc, SCM val)
 {
-  return atomic_exchange (loc, val);
+  return SCM_PACK (atomic_exchange (loc, val));
 }
 static inline _Bool
 scm_atomic_compare_and_swap_scm (SCM *loc, SCM *expected, SCM desired)
 {
-  return atomic_compare_exchange_weak (loc, expected, desired);
+  atomic_uintptr_t *a_loc = (atomic_uintptr_t *) loc;
+  return atomic_compare_exchange_weak (a_loc,
+                                       (uintptr_t *) expected,
+                                       SCM_UNPACK (desired));
 }
 #else /* HAVE_STDATOMIC_H */