From 1933ba0f5dc728f554beb675093126aaef7fbb5a Mon Sep 17 00:00:00 2001
From: Daniel Kraft <d@domob.eu>
Date: Sun, 30 Nov 2008 21:36:10 +0100
Subject: re PR fortran/37779 (Missing RECURSIVE not detected)
2008-11-30 Daniel Kraft <d@domob.eu>
PR fortran/37779
* gfortran.h (struct gfc_entry_list): Fixed typo in comment.
* resolve.c (is_illegal_recursion): New method.
(resolve_procedure_expression): Use new is_illegal_recursion instead of
direct check and handle function symbols correctly.
(resolve_actual_arglist): Removed useless recursion check.
(resolve_function): Use is_illegal_recursion instead of direct check.
(resolve_call): Ditto.
2008-11-30 Daniel Kraft <d@domob.eu>
PR fortran/37779
* gfortran.dg/recursive_check_1.f: Changed expected error message to
the more general new one.
* gfortran.dg/recursive_check_2.f90: Ditto.
* gfortran.dg/entry_18.f90: Ditto.
* gfortran.dg/recursive_check_4.f03: Do "the same" check also for
FUNCTIONS, as this is different in details from SUBROUTINES.
* gfortran.dg/recursive_check_6.f03: New test.
From-SVN: r142299
---
gcc/fortran/resolve.c | 120 ++++++++++++++++++++++++++++++++------------------
1 file changed, 77 insertions(+), 43 deletions(-)
(limited to 'gcc/fortran/resolve.c')
diff --git a/gcc/fortran/resolve.c b/gcc/fortran/resolve.c
index 59e9e54..6ccbe12 100644
--- a/gcc/fortran/resolve.c
+++ b/gcc/fortran/resolve.c
@@ -1073,6 +1073,58 @@ count_specific_procs (gfc_expr *e)
}
+/* See if a call to sym could possibly be a not allowed RECURSION because of
+ a missing RECURIVE declaration. This means that either sym is the current
+ context itself, or sym is the parent of a contained procedure calling its
+ non-RECURSIVE containing procedure.
+ This also works if sym is an ENTRY. */
+
+static bool
+is_illegal_recursion (gfc_symbol* sym, gfc_namespace* context)
+{
+ gfc_symbol* proc_sym;
+ gfc_symbol* context_proc;
+
+ gcc_assert (sym->attr.flavor == FL_PROCEDURE);
+
+ /* If we've got an ENTRY, find real procedure. */
+ if (sym->attr.entry && sym->ns->entries)
+ proc_sym = sym->ns->entries->sym;
+ else
+ proc_sym = sym;
+
+ /* If sym is RECURSIVE, all is well of course. */
+ if (proc_sym->attr.recursive || gfc_option.flag_recursive)
+ return false;
+
+ /* Find the context procdure's "real" symbol if it has entries. */
+ context_proc = (context->entries ? context->entries->sym
+ : context->proc_name);
+ if (!context_proc)
+ return true;
+
+ /* A call from sym's body to itself is recursion, of course. */
+ if (context_proc == proc_sym)
+ return true;
+
+ /* The same is true if context is a contained procedure and sym the
+ containing one. */
+ if (context_proc->attr.contained)
+ {
+ gfc_symbol* parent_proc;
+
+ gcc_assert (context->parent);
+ parent_proc = (context->parent->entries ? context->parent->entries->sym
+ : context->parent->proc_name);
+
+ if (parent_proc == proc_sym)
+ return true;
+ }
+
+ return false;
+}
+
+
/* Resolve a procedure expression, like passing it to a called procedure or as
RHS for a procedure pointer assignment. */
@@ -1081,16 +1133,18 @@ resolve_procedure_expression (gfc_expr* expr)
{
gfc_symbol* sym;
- if (expr->ts.type != BT_PROCEDURE || expr->expr_type != EXPR_VARIABLE)
+ if (expr->expr_type != EXPR_VARIABLE)
return SUCCESS;
gcc_assert (expr->symtree);
+
sym = expr->symtree->n.sym;
- gcc_assert (sym->attr.flavor == FL_PROCEDURE);
+ if (sym->attr.flavor != FL_PROCEDURE
+ || (sym->attr.function && sym->result == sym))
+ return SUCCESS;
/* A non-RECURSIVE procedure that is used as procedure expression within its
own body is in danger of being called recursively. */
- if (!sym->attr.recursive && sym == gfc_current_ns->proc_name
- && !gfc_option.flag_recursive)
+ if (is_illegal_recursion (sym, gfc_current_ns))
gfc_warning ("Non-RECURSIVE procedure '%s' at %L is possibly calling"
" itself recursively. Declare it RECURSIVE or use"
" -frecursive", sym->name, &expr->where);
@@ -1203,15 +1257,6 @@ resolve_actual_arglist (gfc_actual_arglist *arg, procedure_type ptype,
/* Just in case a specific was found for the expression. */
sym = e->symtree->n.sym;
- if (sym->attr.entry && sym->ns->entries
- && sym->ns == gfc_current_ns
- && !sym->ns->entries->sym->attr.recursive)
- {
- gfc_error ("Reference to ENTRY '%s' at %L is recursive, but"
- " procedure '%s' is not declared as RECURSIVE",
- sym->name, &e->where, sym->ns->entries->sym->name);
- }
-
/* If the symbol is the function that names the current (or
parent) scope, then we really have a variable reference. */
@@ -2455,22 +2500,19 @@ resolve_function (gfc_expr *expr)
* call themselves. */
if (expr->value.function.esym && !expr->value.function.esym->attr.recursive)
{
- gfc_symbol *esym, *proc;
+ gfc_symbol *esym;
esym = expr->value.function.esym;
- proc = gfc_current_ns->proc_name;
- if (esym == proc)
- {
- gfc_error ("Function '%s' at %L cannot call itself, as it is not "
- "RECURSIVE", name, &expr->where);
- t = FAILURE;
- }
- if (esym->attr.entry && esym->ns->entries && proc->ns->entries
- && esym->ns->entries->sym == proc->ns->entries->sym)
+ if (is_illegal_recursion (esym, gfc_current_ns))
{
- gfc_error ("Call to ENTRY '%s' at %L is recursive, but function "
- "'%s' is not declared as RECURSIVE",
- esym->name, &expr->where, esym->ns->entries->sym->name);
+ if (esym->attr.entry && esym->ns->entries)
+ gfc_error ("ENTRY '%s' at %L cannot be called recursively, as"
+ " function '%s' is not RECURSIVE",
+ esym->name, &expr->where, esym->ns->entries->sym->name);
+ else
+ gfc_error ("Function '%s' at %L cannot be called recursively, as it"
+ " is not RECURSIVE", esym->name, &expr->where);
+
t = FAILURE;
}
}
@@ -2920,25 +2962,17 @@ resolve_call (gfc_code *c)
/* Subroutines without the RECURSIVE attribution are not allowed to
* call themselves. */
- if (csym && !csym->attr.recursive)
+ if (csym && is_illegal_recursion (csym, gfc_current_ns))
{
- gfc_symbol *proc;
- proc = gfc_current_ns->proc_name;
- if (csym == proc)
- {
- gfc_error ("SUBROUTINE '%s' at %L cannot call itself, as it is not "
- "RECURSIVE", csym->name, &c->loc);
- t = FAILURE;
- }
-
- if (csym->attr.entry && csym->ns->entries && proc->ns->entries
- && csym->ns->entries->sym == proc->ns->entries->sym)
- {
- gfc_error ("Call to ENTRY '%s' at %L is recursive, but subroutine "
- "'%s' is not declared as RECURSIVE",
+ if (csym->attr.entry && csym->ns->entries)
+ gfc_error ("ENTRY '%s' at %L cannot be called recursively, as"
+ " subroutine '%s' is not RECURSIVE",
csym->name, &c->loc, csym->ns->entries->sym->name);
- t = FAILURE;
- }
+ else
+ gfc_error ("SUBROUTINE '%s' at %L cannot be called recursively, as it"
+ " is not RECURSIVE", csym->name, &c->loc);
+
+ t = FAILURE;
}
/* Switch off assumed size checking and do this again for certain kinds
--
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