re PR sanitizer/88426 (Compiler crash if use special code with command line switch -fsanitize=float-cast-overflow)

	PR sanitizer/88426
	* c-convert.c (convert): Call c_fully_fold before calling
	ubsan_instrument_float_cast.

	* c-c++-common/ubsan/float-cast-overflow-11.c: New test.

From-SVN: r267022