| From 8eaf14a17244aaf000b4d19e4fde4a637576939f Mon Sep 17 00:00:00 2001 |
| From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> |
| Date: Sun, 7 Feb 2016 21:40:47 +0100 |
| Subject: [PATCH] configure.ac: check if libatomic is needed |
| |
| The mpd source code uses the C++11 <atomic> functionality, which |
| internally is implemented using the __atomic_*() gcc built-ins. On |
| certain architectures, the __atomic_*() built-ins are implemented in |
| the libatomic library that comes with the rest of the gcc runtime. Due |
| to this, code using <atomic> might need to link against libatomic, |
| otherwise one hits build issues such as: |
| |
| GlobalEvents.cxx:(.text._ZN12GlobalEvents4EmitENS_5EventE+0x14): undefined reference to `__atomic_fetch_or_4' |
| |
| on an architecture like SPARC. |
| |
| To solve this, a configure.ac check is added to know if we need to |
| link against libatomic or not. |
| |
| Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> |
| --- |
| configure.ac | 2 ++ |
| 1 file changed, 2 insertions(+) |
| |
| diff --git a/configure.ac b/configure.ac |
| index 107b45a..8e6fab7 100644 |
| --- a/configure.ac |
| +++ b/configure.ac |
| @@ -233,6 +233,8 @@ if test x$have_pthread_setname_np = xyes; then |
| AC_DEFINE(HAVE_PTHREAD_SETNAME_NP, 1, [Is pthread_setname_np() available?]) |
| fi |
| |
| +AC_SEARCH_LIBS([__atomic_load_4], [atomic]) |
| + |
| dnl --------------------------------------------------------------------------- |
| dnl Event loop selection |
| dnl --------------------------------------------------------------------------- |
| -- |
| 2.6.4 |
| |
