Add autoconf checks for all __atomic builtins that urcu require, and adjust the gcc and clang versions in the README.md.
Signed-off-by: Ondřej Surý <ond...@sury.org> --- README.md | 33 +++++++++------------------------ configure.ac | 15 +++++++++++++++ 2 files changed, 24 insertions(+), 24 deletions(-) diff --git a/README.md b/README.md index ba5bb08..a65a07a 100644 --- a/README.md +++ b/README.md @@ -68,30 +68,15 @@ Should also work on: (more testing needed before claiming support for these OS). -Linux ARM depends on running a Linux kernel 2.6.15 or better, GCC 4.4 or -better. - -The C compiler used needs to support at least C99. The C++ compiler used -needs to support at least C++11. - -The GCC compiler versions 3.3, 3.4, 4.0, 4.1, 4.2, 4.3, 4.4 and 4.5 are -supported, with the following exceptions: - - - GCC 3.3 and 3.4 have a bug that prevents them from generating volatile - accesses to offsets in a TLS structure on 32-bit x86. These versions are - therefore not compatible with `liburcu` on x86 32-bit - (i386, i486, i586, i686). - The problem has been reported to the GCC community: - <http://www.mail-archive.com/gcc-bugs@gcc.gnu.org/msg281255.html> - - GCC 3.3 cannot match the "xchg" instruction on 32-bit x86 build. - See <http://kerneltrap.org/node/7507> - - Alpha, ia64 and ARM architectures depend on GCC 4.x with atomic builtins - support. For ARM this was introduced with GCC 4.4: - <http://gcc.gnu.org/gcc-4.4/changes.html>. - - Linux aarch64 depends on GCC 5.1 or better because prior versions - perform unsafe access to deallocated stack. - -Clang version 3.0 (based on LLVM 3.0) is supported. +Linux ARM depends on running a Linux kernel 2.6.15 or better. + +The C compiler used needs to support at least C99 and __atomic +builtins. The C++ compiler used needs to support at least C++11 +and __atomic builtins. + +The GCC compiler versions 4.7 or better are supported. + +Clang version 3.1 (based on LLVM 3.1) is supported. Glibc >= 2.4 should work but the older version we test against is currently 2.17. diff --git a/configure.ac b/configure.ac index 909cf1d..cb7ba18 100644 --- a/configure.ac +++ b/configure.ac @@ -198,6 +198,21 @@ AC_SEARCH_LIBS([clock_gettime], [rt], [ AC_DEFINE([CONFIG_RCU_HAVE_CLOCK_GETTIME], [1], [clock_gettime() is detected.]) ]) +# Require __atomic builtins +AC_COMPILE_IFELSE( + [AC_LANG_PROGRAM( + [[int x, y;]], + [[__atomic_store_n(&x, 0, __ATOMIC_RELEASE); + __atomic_load_n(&x, __ATOMIC_CONSUME); + y = __atomic_exchange_n(&x, 1, __ATOMIC_ACQ_REL); + __atomic_compare_exchange_n(&x, &y, 0, 0, __ATOMIC_ACQ_REL, __ATOMIC_CONSUME); + __atomic_add_fetch(&x, 1, __ATOMIC_ACQ_REL); + __atomic_sub_fetch(&x, 1, __ATOMIC_ACQ_REL); + __atomic_and_fetch(&x, 0x01, __ATOMIC_ACQ_REL); + __atomic_or_fetch(&x, 0x01, __ATOMIC_ACQ_REL); + __atomic_thread_fence(__ATOMIC_ACQ_REL)]])], + [], + [AC_MSG_ERROR([The compiler does not support __atomic builtins])]) ## ## ## Optional features selection ## -- 2.39.2 _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
