| Summary: | ASTERISK-27619: Build System: Require compiler to provide built-in support for atomic references. | ||
| Reporter: | Corey Farrell (coreyfarrell) | Labels: | |
| Date Opened: | 2018-01-24 14:25:38.000-0600 | Date Closed: | 2018-01-30 06:57:27.000-0600 |
| Priority: | Major | Regression? | |
| Status: | Closed/Complete | Components: | Core/BuildSystem |
| Versions: | GIT | Frequency of Occurrence | |
| Related Issues: | |||
| Environment: | Attachments: | ||
| Description: | I'm working with the jansson project to get thread safe reference counting \[1\]. I'm getting some push-back on the pieces necessary to emulate atomic operations. I'm proposing that Asterisk 16+ should require the availability of __sync or __atomic built-ins:
* __sync_fetch_and_add or __atomic_fetch_add (used by AO2) * __sync_add_and_fetch or __atomic_add_fetch (to be used by jansson) * __sync_lock_test_and_set / __sync_lock_release or the __atomic equivalents (used by spinlock.h) All of these __sync functions have been available since gcc-4.1.2 \[2\] (released in 2007). The __atomic variants are newer and I believe they should be preferred if available. This is in preparation for Asterisk 16+ hopefully requiring jansson 2.11+ and removing most (or all) locking from main/json.c. \[1\]: https://github.com/akheron/jansson/pull/389 \[2\]: https://gcc.gnu.org/onlinedocs/gcc-4.1.2/gcc/Atomic-Builtins.html | ||
| Comments: | By: Friendly Automation (friendly-automation) 2018-01-30 06:57:28.465-0600 Change 8049 merged by Jenkins2: Build System: Require __sync or __atomic functions. [https://gerrit.asterisk.org/8049|https://gerrit.asterisk.org/8049] By: Friendly Automation (friendly-automation) 2018-01-31 17:08:16.212-0600 Change 8107 merged by Jenkins2: core: Create ast_atomic macro's. [https://gerrit.asterisk.org/8107|https://gerrit.asterisk.org/8107] | ||