[PATCH] lto: no sub-make when --jobserver-auth= is missing

[Martin Liška]

We newly correctly detect that a job server is not active for
a LTO linking:

lto-wrapper: warning: jobserver is not available: '--jobserver-auth=' is not 
present in 'MAKEFLAGS'

In that situation we should not call make -f abc.mk as it can leed
to N^2 LTRANS units.

Ready for master?
Thanks,
Martin

gcc/ChangeLog:

        * lto-wrapper.c (run_gcc): Do not use sub-make when jobserver is
        not detected properly.
---
 gcc/lto-wrapper.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/gcc/lto-wrapper.c b/gcc/lto-wrapper.c
index b2af3caa021..fe10f4f4fbb 100644
--- a/gcc/lto-wrapper.c
+++ b/gcc/lto-wrapper.c
@@ -1582,7 +1582,11 @@ run_gcc (unsigned argc, char *argv[])
     {
       const char *jobserver_error = jobserver_active_p ();
       if (jobserver && jobserver_error != NULL)
-       warning (0, jobserver_error);
+       {
+         warning (0, jobserver_error);
+         parallel = 0;
+         jobserver = 0;
+       }
       else if (!jobserver && jobserver_error == NULL)
        {
          parallel = 1;
--
2.29.0