re PR c/59891 (ICE on invalid code (with div-by-zero) at all optimization levels on x86_64-linux-gnu)

	PR c/59891
c/
	* c-typeck.c (build_conditional_expr): Call c_fully_fold instead
	of remove_c_maybe_const_expr on op1 and op2.
testsuite/
	* gcc.dg/torture/pr59891.c: New test.

From-SVN: r206944