On 18 Jan 2023, at 23:16, Ludovic Courtès <ludo@gnu.org> wrote:
Hi Daniel,
lloda <lloda@sarc.name> skribis:
.../libguile/threads.h:194:43: error: 'scm_i_current_thread' is defined with tls model global-dynamic
194 | SCM_INTERNAL SCM_THREAD_LOCAL scm_thread *scm_i_current_thread;
| ^
.../libguile/threads.c:357:30: note: previously defined here as local-dynamic
357 | SCM_THREAD_LOCAL scm_thread *scm_i_current_thread = NULL;
Simply repeating SCM_INTERNAL in the .c fixes it...
The problem is that ‘SCM_INTERNAL’ is synonymous with ‘extern’, which
makes no sense for a definition (threads.c:357), so rightfully GCC
GNU/Linux rightfully complains:
--8<---------------cut here---------------start------------->8---
CC libguile_3.0_la-threads.lo
threads.c:358:43: warning: 'scm_i_current_thread' initialized and declared 'extern'
358 | SCM_INTERNAL SCM_THREAD_LOCAL scm_thread *scm_i_current_thread = NULL;
| ^~~~~~~~~~~~~~~~~~~~
--8<---------------cut here---------------end--------------->8---
It’s just a warning, but still not looking good.
Hi,
Agreed, I had the same warning on mac os. Looked like the least bad choice...
Is there something else at play, such as a ‘-ftls-model’ flag being
passed to GCC somehow (info “(gcc) Code Gen Options")?
If not, should we have:
#define SCM_THREAD_LOCAL \
__thread __attribute__ ((__tls_model__ ("global-dynamic")))
instead (info "(gcc) Common Variable Attributes")?
Would that work with Clang?
Ludo’.
I don't seem to have any such flags.
The attribute does fix the issue on mac os with gcc 12.
I hadn't tried clang before, but I did now, and clang 14 works fine with or without the attribute. So the fix would only be for gcc.
Thanks
Daniel |