Please describe the problem:
When I compile a program that uses g_static_mutex_lock it gives me a warning: dereferencing type-punned pointer will break strict-aliasing rules

Steps to reproduce:
1. Set gcc options to "std=c99 -Wall -O2"
2. Add a "static GStaticMutex test_mutex = G_STATIC_MUTEX_INIT;"
3. Add code like "g_static_mutex_lock(&test_mutex);"


Actual results:
Prints the warning: "dereferencing type-punned pointer will break strict-aliasing rules"

Expected results:
No warning should be emitted.

Does this happen every time?
Yes.

Other information: