libcilkrts.so fails to link on Solaris 9/x86 with Sun as since this
configuration lacks visibility support:
Text relocation remains referenced
against symbol offset in file
__cilkrts_get_tls_worker 0x41 .libs/cilk-abi.o
__cilkrts_get_tls_worker 0x254 .libs/cilk-abi.o
__cilkrts_get_tls_worker 0x5c9 .libs/cilk-abi.o
__cilkrts_get_tls_worker 0x609 .libs/cilk-abi.o
__cilkrts_get_tls_worker 0x6e7 .libs/cilk-abi.o
__cilkrts_get_tls_worker 0x774 .libs/cilk-abi.o
__cilkrts_get_tls_worker 0x271 .libs/cilk-abi-cilk-for.o
__cilkrts_get_tls_worker 0x361 .libs/cilk-abi-cilk-for.o
__cilkrts_get_tls_worker 0x10 .libs/cilk_api.o
__cilkrts_get_tls_worker 0xc1 .libs/cilk_api.o
__cilkrts_get_tls_worker 0x194 .libs/cilk_api.o
__cilkrts_get_tls_worker 0x241 .libs/cilk_api.o
__cilkrts_get_tls_worker 0x324 .libs/cilk_api.o
__cilkrts_get_tls_worker 0x706 .libs/reducer_impl.o
__cilkrts_get_tls_worker 0x893 .libs/reducer_impl.o
[...]
__cilkrts_bump_worker_rank_internal 0x32c .libs/cilk_api.o
__cilkrts_init_worker_sysdep 0x262c .libs/scheduler.o
ld: fatal: relocations remain against allocatable but non-writable sections
collect2: error: ld returned 1 exit status
make[2]: *** [libcilkrts.la] Error 1
During the build, one sees many warnings like this:
/vol/gcc/src/hg/trunk/local/libcilkrts/runtime/cilk-abi.c: In function '__cilkrt
s_enter_frame_fast':
/vol/gcc/src/hg/trunk/local/libcilkrts/runtime/cilk-abi.c:144:1: warning: visibi
lity attribute not supported in this configuration; ignored [-Wattributes]
This can be cured by actually checking if a given configuration supports
__attribute((visibility)) instead of just assuming gcc on Unix systems
does. The following patch does just that.
Tested by reconfiguring and rebuilding libcilkrts on i386-pc-solaris2.9
(which now builds) and i386-pc-solaris2.11 (where elfdump -s still show
many symbols as protected as they should be).
Ok for mainline?
Rainer
2013-11-14 Rainer Orth <[email protected]>
* configure.ac (libcilkrts_cv_have_attribute_visibility): Check
for __attribute__((visibility)).
* configure: Regenerate.
* include/cilk/common.h (CILK_EXPORT, CILK_EXPORT_DATA): Only use
__attribute__((visibility)) if HAVE_ATTRIBUTE_VISIBILITY.
# HG changeset patch
# Parent fc2fe9ba5a63f3442f35bc4dc8cfece05c7577ca
Only use visibility if supported
diff --git a/libcilkrts/configure.ac b/libcilkrts/configure.ac
--- a/libcilkrts/configure.ac
+++ b/libcilkrts/configure.ac
@@ -54,6 +54,18 @@ AC_CONFIG_FILES([Makefile])
AM_ENABLE_MULTILIB(, ..)
AC_FUNC_ALLOCA
+# Check whether the target supports protected visibility.
+save_CFLAGS="$CFLAGS"
+CFLAGS="$CFLAGS -Werror"
+AC_TRY_COMPILE([void __attribute__((visibility("protected"))) foo(void) { }],
+ [], libcilkrts_cv_have_attribute_visibility=yes,
+ libcilkrts_cv_have_attribute_visibility=no)
+CFLAGS="$save_CFLAGS"
+if test $libcilkrts_cv_have_attribute_visibility = yes; then
+ AC_DEFINE(HAVE_ATTRIBUTE_VISIBILITY, 1,
+ [Define to 1 if the target supports __attribute__((visibility(...))).])
+fi
+
# Get target configury.
. ${srcdir}/configure.tgt
if test -n "$UNSUPPORTED"; then
diff --git a/libcilkrts/include/cilk/common.h b/libcilkrts/include/cilk/common.h
--- a/libcilkrts/include/cilk/common.h
+++ b/libcilkrts/include/cilk/common.h
@@ -101,7 +101,7 @@ namespace cilk {
# define CILK_EXPORT /* nothing */
# define CILK_EXPORT_DATA /* nothing */
#else /* Unix/gcc */
-# ifdef IN_CILK_RUNTIME
+# if defined(IN_CILK_RUNTIME) && defined(HAVE_ATTRIBUTE_VISIBILITY)
# define CILK_EXPORT __attribute__((visibility("protected")))
# define CILK_EXPORT_DATA __attribute__((visibility("protected")))
# else
--
-----------------------------------------------------------------------------
Rainer Orth, Center for Biotechnology, Bielefeld University
