openmp: Handle clauses with gimple sequences in convert_nonlocal_omp_clauses properly

openmp: Handle clauses with gimple sequences in convert_nonlocal_omp_clauses properly

If the walk_body on the various sequences of reduction, lastprivate and/or linear
clauses needs to create a temporary variable, we should declare that variable
in that sequence rather than outside, where it would need to be privatized inside of
the construct.

2020-08-08  Jakub Jelinek  <jakub@redhat.com>

	PR fortran/93553
	* tree-nested.c (convert_nonlocal_omp_clauses): For
	OMP_CLAUSE_REDUCTION, OMP_CLAUSE_LASTPRIVATE and OMP_CLAUSE_LINEAR
	save info->new_local_var_chain around walks of the clause gimple
	sequences and declare_vars if needed into the sequence.

2020-08-08  Tobias Burnus  <tobias@codesourcery.com>

	PR fortran/93553
	* testsuite/libgomp.fortran/pr93553.f90: New test.

(cherry picked from commit 676b5525e8333005bdc1c596ed086f1da27a450f)