Fortran: improve checks of NULL without MOLD as actual argument [PR104819]
gcc/fortran/ChangeLog:
PR fortran/104819
* check.cc (gfc_check_null): Handle nested NULL()s.
(is_c_interoperable): Check for MOLD argument of NULL() as part of
the interoperability check.
* interface.cc (gfc_compare_actual_formal): Extend checks for NULL()
actual arguments for presence of MOLD argument when required by
Interp J3/22-146.
gcc/testsuite/ChangeLog:
PR fortran/104819
* gfortran.dg/assumed_rank_9.f90: Adjust testcase use of NULL().
* gfortran.dg/pr101329.f90: Adjust testcase to conform to interp.
* gfortran.dg/null_actual_4.f90: New test.
(cherry picked from commit
db0b6746be075e43c8142585968483e125bb52d0)