[patch] lto-wrapper: Honor -save-temps for ltrans' makefile

[Tobias Burnus]

Noticed that -save-tmp is ignored for parallel LTO. With this patch, the 
result is now:

make -f ./a.ltrans.mk -j2 all
[Leaving LTRANS ./a.ltrans.mk]
instead of

make -f /tmp/ccXgtcjJ.mk -j2 all
[Leaving LTRANS /tmp/ccXgtcjJ.mk]

OK for mainline?

Tobias
lto-wrapper: Honor -save-temps for ltrans' makefile

gcc/ChangeLog:

	* lto-wrapper.cc (run_gcc): Honor -save-temps for
	makefile name.

diff --git a/gcc/lto-wrapper.cc b/gcc/lto-wrapper.cc
index 6bfc96590a5..c07765b37a2 100644
--- a/gcc/lto-wrapper.cc
+++ b/gcc/lto-wrapper.cc
@@ -1994,7 +1994,10 @@ cont:
 
       if (parallel)
 	{
-	  makefile = make_temp_file (".mk");
+	  if (save_temps)
+	    makefile = concat (dumppfx, "ltrans.mk", NULL);
+	  else
+	    makefile = make_temp_file (".mk");
 	  mstream = fopen (makefile, "w");
 	  qsort (ltrans_priorities, nr, sizeof (int) * 2, cmp_priority);
 	}