From 59a63247992eb13153b82c4902aadf111460eac2 Mon Sep 17 00:00:00 2001 From: Harald Anlauf Date: Thu, 10 Nov 2022 22:30:27 +0100 Subject: Fortran: fix treatment of character, value, optional dummy arguments [PR107444] Fix handling of character dummy arguments that have the optional+value attribute. Change name of internal symbols that carry the hidden presence status of optional arguments to distinguish them from the internal hidden character length. Update documentation to clarify the gfortran ABI. gcc/fortran/ChangeLog: PR fortran/107444 * trans-decl.cc (create_function_arglist): Extend presence status to all intrinsic types, and change prefix of internal symbol to '.'. * trans-expr.cc (gfc_conv_expr_present): Align to changes in create_function_arglist. (gfc_conv_procedure_call): Fix generation of procedure arguments for the case of character dummy arguments with optional+value attribute. * trans-types.cc (gfc_get_function_type): Synchronize with changes to create_function_arglist. * doc/gfortran/naming-and-argument-passing-conventions.rst: Clarify the gfortran argument passing conventions with regard to OPTIONAL dummy arguments of intrinsic type. gcc/testsuite/ChangeLog: PR fortran/107444 * gfortran.dg/optional_absent_7.f90: Adjust regex. * gfortran.dg/optional_absent_8.f90: New test. --- gcc/fortran/trans-expr.cc | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) (limited to 'gcc/fortran/trans-expr.cc') diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc index f3fbb52..b95c5cf 100644 --- a/gcc/fortran/trans-expr.cc +++ b/gcc/fortran/trans-expr.cc @@ -1985,15 +1985,14 @@ gfc_conv_expr_present (gfc_symbol * sym, bool use_saved_desc) /* Intrinsic scalars with VALUE attribute which are passed by value use a hidden argument to denote the present status. */ - if (sym->attr.value && sym->ts.type != BT_CHARACTER - && sym->ts.type != BT_CLASS && sym->ts.type != BT_DERIVED - && !sym->attr.dimension) + if (sym->attr.value && !sym->attr.dimension + && sym->ts.type != BT_CLASS && !gfc_bt_struct (sym->ts.type)) { char name[GFC_MAX_SYMBOL_LEN + 2]; tree tree_name; gcc_assert (TREE_CODE (decl) == PARM_DECL); - name[0] = '_'; + name[0] = '.'; strcpy (&name[1], sym->name); tree_name = get_identifier (name); @@ -6162,11 +6161,21 @@ gfc_conv_procedure_call (gfc_se * se, gfc_symbol * sym, value, pass "0" and a hidden argument gives the optional status. */ if (fsym && fsym->attr.optional && fsym->attr.value - && !fsym->attr.dimension && fsym->ts.type != BT_CHARACTER - && fsym->ts.type != BT_CLASS && fsym->ts.type != BT_DERIVED) + && !fsym->attr.dimension && fsym->ts.type != BT_CLASS + && !gfc_bt_struct (sym->ts.type)) { - parmse.expr = fold_convert (gfc_sym_type (fsym), - integer_zero_node); + if (fsym->ts.type == BT_CHARACTER) + { + /* Pass a NULL pointer for an absent CHARACTER arg + and a length of zero. */ + parmse.expr = null_pointer_node; + parmse.string_length + = build_int_cst (gfc_charlen_type_node, + 0); + } + else + parmse.expr = fold_convert (gfc_sym_type (fsym), + integer_zero_node); vec_safe_push (optionalargs, boolean_false_node); } else -- cgit v1.1