Bug 17376 – modify global variable with pure method

Consider this test code: int ga; struct Tester { int* pa; this(int) { pa = &ga; } void test() pure { *pa = 3; } } void main() { auto t = Tester(1); assert(ga == 0); t.test(); assert(ga == 3); } From the perspective of the caller, he is calling a pure function, but can observe a global state change. It is also possible to change a static member of the struct in the same manner. I guess that this inhibits some opportunities for optimizations.

This compiles successfully because the 'this' reference is treated like any other parameter.