* tests/test-totalorder.h: Include <math.h>.
(positive_NaN_with_payload, negative_NaN_with_payload): New functions.
(main): Test quiet NaNs of each sign with different payload.
* tests/test-totalorder.c (TOTALORDER_POSITIVE_NAN,
TOTALORDER_NEGATIVE_NAN): Remove macros.
(TOTALORDER_SETPAYLOAD): New macro.
* tests/test-totalorderf.c (TOTALORDER_POSITIVE_NAN,
TOTALORDER_NEGATIVE_NAN): Remove macros.
(TOTALORDER_SETPAYLOAD): New macro.
* tests/test-totalorderl.c (TOTALORDER_POSITIVE_NAN,
TOTALORDER_NEGATIVE_NAN): Remove macros.
(TOTALORDER_SETPAYLOAD): New macro.
* modules/totalorder-tests (Depends-on): Add setpayload.
(Makefile.am): Link test-totalorder with $(SETPAYLOAD_LIBM).
* modules/totalorderf-tests (Depends-on): Add setpayloadf.
(Makefile.am): Link test-totalorderf with $(SETPAYLOADF_LIBM).
* modules/totalorderl-tests (Depends-on): Add setpayloadl.
(Makefile.am): Link test-totalorderl with $(SETPAYLOADL_LIBM).