re PR ipa/77905 (ICE at -Os and above in both 32-bit and 64-bit modes on x86_64-linux-gnu (internal compiler error: in ipa_comdats, at ipa-comdats.c:352))

	PR ipa/77905
	* ipa-pure-const.c (cdtor_p): Return true for
	DECL_STATIC_{CON,DE}STRUCTOR even when it is
	DECL_LOOPING_CONST_OR_PURE_P.

	* g++.dg/ipa/pr77905.C: New test.

From-SVN: r243596