https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105030
--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
something like
void *bar (void *x)
{
*(double *)x = 1.;
}
void foo(int n)
{
double atemp;
pthread_create (..., bar, &atemp);
for (int i = 0; i < n; i++)
if (a[i] < atemp)
atemp = a[i];
pthread_join (...);
if (atemp != 1.)
abort ();
}
if it is ensured the store to atemp in the loop never takes place then
we have created a store data race when applying store motion. Of course
thread creation/join can be hidden in other functions called from foo()
as long as 'atemp' escapes to callers.
