[Bug lto/98275] -flto=auto fails if nthreads_var is zero, must not pass -j0

[marxin at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98275

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |11.0
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2020-12-14
     Ever confirmed|0                           |1
           Assignee|unassigned at gcc dot gnu.org      |marxin at gcc dot 
gnu.org

--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
Thank you for the bug report.

Can you please test the following patch:

diff --git a/gcc/lto-wrapper.c b/gcc/lto-wrapper.c
index 68ccb156521..da1305c1696 100644
--- a/gcc/lto-wrapper.c
+++ b/gcc/lto-wrapper.c
@@ -1780,6 +1780,8 @@ cont1:
        {
          char buf[256];
          init_num_threads ();
+         if (nthreads_var == 0)
+           nthreads_var = 1;
          if (verbose)
            fprintf (stderr, "LTO parallelism level set to %ld\n",
                     nthreads_var);