gcc/c-family/ChangeLog:

	PR c/89812
	* c-common.c (check_user_alignment): Rename local.  Correct maximum
	alignment in diagnostic.  Avoid assuming argument fits in SHWI,
	convert it to UHWI when it fits.

gcc/testsuite/ChangeLog:

	PR c/89812
	* gcc.dg/attr-aligned-3.c: New test.

From-SVN: r269927