gdb.threads/multi-create: Double the existing stack size.

Setting the stack size to 2*PTHREAD_STACK_MIN actually lowered the
stack on FreeBSD rather than raising it causing non-main threads in
the test program to overflow their stack and crash.  Double the
existing stack size rather than assuming that the initial stack size
is PTHREAD_STACK_MIN.

1 files changed, 6 insertions, 2 deletions

diff --git a/gdb/testsuite/gdb.threads/multi-create.c b/gdb/testsuite/gdb.threads/multi-create.c
index f4a47c3..9944ba5 100644
--- a/gdb/testsuite/gdb.threads/multi-create.c
+++ b/gdb/testsuite/gdb.threads/multi-create.c
@@ -39,11 +39,13 @@ create_function (void *arg)
   pthread_attr_t attr;
   pthread_t threads[NUM_THREAD];
   int args[NUM_THREAD];
+  size_t stacksize;
   int i = * (int *) arg;
   int j;
 
   pthread_attr_init (&attr); /* set breakpoint 1 here.  */
-  pthread_attr_setstacksize (&attr, 2*PTHREAD_STACK_MIN);
+  pthread_attr_getstacksize (&attr, &stacksize);
+  pthread_attr_setstacksize (&attr, 2 * stacksize);
 
   /* Create a ton of quick-executing threads, then wait for them to
      complete.  */
@@ -67,10 +69,12 @@ main (int argc, char **argv)
   pthread_attr_t attr;
   pthread_t threads[NUM_CREATE];
   int args[NUM_CREATE];
+  size_t stacksize;
   int n, i;
 
   pthread_attr_init (&attr);
-  pthread_attr_setstacksize (&attr, 2*PTHREAD_STACK_MIN);
+  pthread_attr_getstacksize (&attr, &stacksize);
+  pthread_attr_setstacksize (&attr, 2 * stacksize);
 
   for (n = 0; n < 100; ++n)
     {