c-opts.c (c_common_post_options): Set -ffp-contract=off in C standards modes.

c-opts.c (c_common_post_options): Set -ffp-contract=off in C standards modes.

c-family:
	* c-opts.c (c_common_post_options): Set -ffp-contract=off in C
	standards modes.
	* c-cppbuiltin.c (cpp_iec_559_value): Consider -ffp-contract=fast
	to mean lack of IEEE 754 support.

testsuite:
	* gcc.dg/torture/c99-contract-1.c: New test.

From-SVN: r204460