[Mesa-dev] [PATCH,v3] configure.ac/meson.build: Fix -latomic test
Nicolas Boichat
drinkcat at chromium.org
Thu Apr 5 01:33:09 UTC 2018
When compiling with LLVM 6.0 on x86 (32-bit) for Android, the test
fails to detect that -latomic is actually required, as the atomic
call is inlined.
In the code itself (src/util/disk_cache.c), we see this pattern:
p_atomic_add(cache->size, - (uint64_t)size);
where cache->size is an uint64_t *, and results in the following
link time error without -latomic:
src/util/disk_cache.c:628: error: undefined reference to '__atomic_fetch_add_8'
Fix the configure/meson test to replicate this pattern, which then
correctly realizes the need for -latomic.
Signed-off-by: Nicolas Boichat <drinkcat at chromium.org>
---
Changes since v1:
- Updated meson.build as well (untested)
Changes since v2:
- Moved * with the v in configure.ac
configure.ac | 6 ++++--
meson.build | 6 ++++--
2 files changed, 8 insertions(+), 4 deletions(-)
diff --git a/configure.ac b/configure.ac
index e874f8ebfb2..69981a6f3dd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -445,9 +445,11 @@ if test "x$GCC_ATOMIC_BUILTINS_SUPPORTED" = x1; then
AC_MSG_CHECKING(whether -latomic is needed)
AC_LINK_IFELSE([AC_LANG_SOURCE([[
#include <stdint.h>
- uint64_t v;
+ struct {
+ uint64_t *v;
+ } x;
int main() {
- return (int)__atomic_load_n(&v, __ATOMIC_ACQUIRE);
+ return (int)__atomic_load_n(x.v, __ATOMIC_ACQUIRE);
}]])], GCC_ATOMIC_BUILTINS_NEED_LIBATOMIC=no, GCC_ATOMIC_BUILTINS_NEED_LIBATOMIC=yes)
AC_MSG_RESULT($GCC_ATOMIC_BUILTINS_NEED_LIBATOMIC)
if test "x$GCC_ATOMIC_BUILTINS_NEED_LIBATOMIC" = xyes; then
diff --git a/meson.build b/meson.build
index ee2b4151e2f..c73b20f986c 100644
--- a/meson.build
+++ b/meson.build
@@ -845,8 +845,10 @@ if cc.compiles('int main() { int n; return __atomic_load_n(&n, __ATOMIC_ACQUIRE)
# as ARM.
if not cc.links('''#include <stdint.h>
int main() {
- uint64_t n;
- return (int)__atomic_load_n(&n, __ATOMIC_ACQUIRE);
+ struct {
+ uint64_t *v;
+ } x;
+ return (int)__atomic_load_n(x.v, __ATOMIC_ACQUIRE);
}''',
name : 'GCC atomic builtins required -latomic')
dep_atomic = cc.find_library('atomic')
--
2.17.0.484.g0c8726318c-goog
More information about the mesa-dev
mailing list