Make the system C11 atomics headers fully compatible with external GCC.
The <sys/cdefs.h> and <stdatomic.h> headers already included support for C11 atomics via intrinsincs in modern versions of GCC, but these versions tried to "hide" atomic variables inside a wrapper structure. This wrapper is not compatible with GCC's internal <stdatomic.h> header, so that if GCC's <stdatomic.h> was used together with <sys/cdefs.h>, use of C11 atomics would fail to compile. Fix this by not hiding atomic variables in a structure for modern versions of GCC. The headers already avoid using a wrapper structure on clang. Note that this wrapper was only used if C11 was not enabled (e.g. via -std=c99), so this also fixes compile failures if a modern version of GCC was used with -std=c11 but with FreeBSD's <stdatomic.h> instead of GCC's <stdatomic.h> and this change fixes that case as well. Reported by: Mark Millard Reviewed by: kib Differential Revision: https://reviews.freebsd.org/D16585
This commit is contained in:
parent
1979b51141
commit
d2aec9714a
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=337399
@ -268,7 +268,7 @@
|
||||
#endif
|
||||
|
||||
#if !defined(__cplusplus) && !__has_extension(c_atomic) && \
|
||||
!__has_extension(cxx_atomic)
|
||||
!__has_extension(cxx_atomic) && !__GNUC_PREREQ__(4, 7)
|
||||
/*
|
||||
* No native support for _Atomic(). Place object in structure to prevent
|
||||
* most forms of direct non-atomic access.
|
||||
|
@ -171,12 +171,9 @@ atomic_signal_fence(memory_order __order __unused)
|
||||
/* Atomics in kernelspace are always lock-free. */
|
||||
#define atomic_is_lock_free(obj) \
|
||||
((void)(obj), (_Bool)1)
|
||||
#elif defined(__CLANG_ATOMICS)
|
||||
#elif defined(__CLANG_ATOMICS) || defined(__GNUC_ATOMICS)
|
||||
#define atomic_is_lock_free(obj) \
|
||||
__atomic_is_lock_free(sizeof(*(obj)), obj)
|
||||
#elif defined(__GNUC_ATOMICS)
|
||||
#define atomic_is_lock_free(obj) \
|
||||
__atomic_is_lock_free(sizeof((obj)->__val), &(obj)->__val)
|
||||
#else
|
||||
#define atomic_is_lock_free(obj) \
|
||||
((void)(obj), sizeof((obj)->__val) <= sizeof(void *))
|
||||
@ -260,28 +257,28 @@ typedef _Atomic(__uintmax_t) atomic_uintmax_t;
|
||||
#elif defined(__GNUC_ATOMICS)
|
||||
#define atomic_compare_exchange_strong_explicit(object, expected, \
|
||||
desired, success, failure) \
|
||||
__atomic_compare_exchange_n(&(object)->__val, expected, \
|
||||
__atomic_compare_exchange_n(object, expected, \
|
||||
desired, 0, success, failure)
|
||||
#define atomic_compare_exchange_weak_explicit(object, expected, \
|
||||
desired, success, failure) \
|
||||
__atomic_compare_exchange_n(&(object)->__val, expected, \
|
||||
__atomic_compare_exchange_n(object, expected, \
|
||||
desired, 1, success, failure)
|
||||
#define atomic_exchange_explicit(object, desired, order) \
|
||||
__atomic_exchange_n(&(object)->__val, desired, order)
|
||||
__atomic_exchange_n(object, desired, order)
|
||||
#define atomic_fetch_add_explicit(object, operand, order) \
|
||||
__atomic_fetch_add(&(object)->__val, operand, order)
|
||||
__atomic_fetch_add(object, operand, order)
|
||||
#define atomic_fetch_and_explicit(object, operand, order) \
|
||||
__atomic_fetch_and(&(object)->__val, operand, order)
|
||||
__atomic_fetch_and(object, operand, order)
|
||||
#define atomic_fetch_or_explicit(object, operand, order) \
|
||||
__atomic_fetch_or(&(object)->__val, operand, order)
|
||||
__atomic_fetch_or(object, operand, order)
|
||||
#define atomic_fetch_sub_explicit(object, operand, order) \
|
||||
__atomic_fetch_sub(&(object)->__val, operand, order)
|
||||
__atomic_fetch_sub(object, operand, order)
|
||||
#define atomic_fetch_xor_explicit(object, operand, order) \
|
||||
__atomic_fetch_xor(&(object)->__val, operand, order)
|
||||
__atomic_fetch_xor(object, operand, order)
|
||||
#define atomic_load_explicit(object, order) \
|
||||
__atomic_load_n(&(object)->__val, order)
|
||||
__atomic_load_n(object, order)
|
||||
#define atomic_store_explicit(object, desired, order) \
|
||||
__atomic_store_n(&(object)->__val, desired, order)
|
||||
__atomic_store_n(object, desired, order)
|
||||
#else
|
||||
#define __atomic_apply_stride(object, operand) \
|
||||
(((__typeof__((object)->__val))0) + (operand))
|
||||
|
Loading…
Reference in New Issue
Block a user