Add main executable symbol uprobe to uprobes_lib.exp test.

There was nothing wrong with the probe itself, but because the body
was empty the compiler optimised away the actual call...

* testsuite/systemtap.base/uprobes_lib.exp: Activate main exe probe, expect
  more output.
* testsuite/systemtap.base/uprobes_lib.stp: Also probe main and main_lib.
* testsuite/systemtap.base/uprobes_exe.c: Put some code in main_func.
* testsuite/systemtap.base/uprobes_lib.c: Likewise for lib_func.

1 files changed, 5 insertions, 3 deletions

diff --git a/testsuite/systemtap.base/uprobes_exe.c b/testsuite/systemtap.base/uprobes_exe.c
index 447434c6..b4811335 100644
--- a/testsuite/systemtap.base/uprobes_exe.c
+++ b/testsuite/systemtap.base/uprobes_exe.c
@@ -15,13 +15,15 @@ int lib_main (void);
 void
 main_func (int foo)
 {
-  ; // nothing here...
+  if (foo > 1)
+    main_func (foo - 1);
+  else
+    lib_main();
 }
 
 int
 main (int argc, char *argv[], char *envp[])
 {
-  main_func(1);
-  lib_main();
+  main_func (3);
   return 0;
 }