stor-layout.c (layout_decl): Use the field's type to determine the mode and keep DECL_BIT_FIELD for a...

	* stor-layout.c (layout_decl): Use the field's type to
	determine the mode and keep DECL_BIT_FIELD for a volatile
	bit-field.
	* config/arm/arm.c (arm_override_options): Default to
	-fstrict-volatile-bitfields.

	testsuite/
	* gcc.target/arm/volatile-bitfields-1.c: New test.
	* gcc.target/arm/volatile-bitfields-2.c: New test.
	* gcc.target/arm/volatile-bitfields-3.c: New test.

From-SVN: r165934