Fortran: make STAT/LSTAT/FSTAT intrinsics generic [PR82480]

Fortran: make STAT/LSTAT/FSTAT intrinsics generic [PR82480]

	PR fortran/82480

gcc/fortran/ChangeLog:

	* check.cc (error_unsupported_kind): Helper function to report an
	unsupported kind of an argument.
	(check_minrange4): Helper function to report if an integer variable
	does not have a decimal range of at least four.
	(gfc_check_fstat): Adjust checks for generalization of instrinsic
	function FSTAT.
	(gfc_check_fstat_sub): Likewise for subroutine FSTAT.
	(gfc_check_stat): Likewise for functio STAT.
	(gfc_check_stat_sub): Likewise for subroutine STAT.
	* intrinsic.texi: Document generalized versions of intrinsics
	STAT/LSTAT/FSTAT.
	* iresolve.cc (gfc_resolve_stat): STAT function result shall have
	the same kind as the VALUES argument.
	(gfc_resolve_lstat): Likewise for LSTAT.
	(gfc_resolve_fstat): Likewise for FSTAT.
	(gfc_resolve_stat_sub): Resolve proper library subroutine for STAT.
	(gfc_resolve_lstat_sub): Likewise for LSTAT.
	* trans-decl.cc (gfc_build_intrinsic_function_decls): Declare
	fndecls for required subroutines in runtine library.
	* trans-intrinsic.cc (conv_intrinsic_fstat_lstat_stat_sub): Emit
	runtime wrapper code for the library functions, taking care of
	possible kind conversion of the optional STATUS argument of the
	subroutine versions of the intrinsics.
	(gfc_conv_intrinsic_subroutine): Use it.
	* trans.h (GTY): Declare prototypes.

gcc/testsuite/ChangeLog:

	* gfortran.dg/stat_3.f90: Extend argument checking.
	* gfortran.dg/stat_4.f90: New test.