Add explanatory comment to set_tid_address wrapper.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@3037 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/coregrind/vg_syscalls.c b/coregrind/vg_syscalls.c
index 66cf3b1..342d379 100644
--- a/coregrind/vg_syscalls.c
+++ b/coregrind/vg_syscalls.c
@@ -1128,6 +1128,14 @@
PRE(sys_set_tid_address, Special)
{
+ // We don't let this syscall run, and don't do anything to simulate it
+ // ourselves -- it becomes a no-op! Why? Tom says:
+ //
+ // I suspect this is deliberate given that all the user level threads
+ // are running in the same kernel thread under valgrind so we probably
+ // don't want to be calling the actual system call here.
+ //
+ // Hmm.
PRINT("sys_set_tid_address ( %p )", arg1);
PRE_REG_READ1(long, "set_tid_address", int *, tidptr);
}