From d8f6c48ccb85ecc0d97a84c32b7a1b8f43c64fe4 Mon Sep 17 00:00:00 2001
From: Harald Anlauf <anlauf@gmx.de>
Date: Mon, 27 Dec 2021 23:06:18 +0100
Subject: [PATCH] Fortran: avoid several NULL pointer dereferences during error
recovery
gcc/fortran/ChangeLog:
PR fortran/102332
* expr.c (gfc_get_variable_expr): Avoid NULL pointer dereferences
during handling of errors with invalid uses of CLASS variables.
* match.c (select_type_set_tmp): Likewise.
* primary.c (gfc_match_varspec): Likewise.
* resolve.c (resolve_variable): Likewise.
(resolve_select_type): Likewise.
gcc/testsuite/ChangeLog:
PR fortran/102332
* gfortran.dg/pr102332.f90: New test.
---
gcc/fortran/expr.c | 3 +-
gcc/fortran/match.c | 3 +-
gcc/fortran/primary.c | 1 +
gcc/fortran/resolve.c | 9 +++-
gcc/testsuite/gfortran.dg/pr102332.f90 | 69 ++++++++++++++++++++++++++
5 files changed, 81 insertions(+), 4 deletions(-)
create mode 100644 gcc/testsuite/gfortran.dg/pr102332.f90
diff --git a/gcc/fortran/expr.c b/gcc/fortran/expr.c
index b874607db1d2..c1258e0eb063 100644
--- a/gcc/fortran/expr.c
+++ b/gcc/fortran/expr.c
@@ -5166,7 +5166,8 @@ gfc_get_variable_expr (gfc_symtree *var)
if (var->n.sym->attr.flavor != FL_PROCEDURE
&& ((var->n.sym->as != NULL && var->n.sym->ts.type != BT_CLASS)
- || (var->n.sym->ts.type == BT_CLASS && CLASS_DATA (var->n.sym)
+ || (var->n.sym->ts.type == BT_CLASS && var->n.sym->ts.u.derived
+ && CLASS_DATA (var->n.sym)
&& CLASS_DATA (var->n.sym)->as)))
{
e->rank = var->n.sym->ts.type == BT_CLASS
diff --git a/gcc/fortran/match.c b/gcc/fortran/match.c
index 617fb35c9cd1..41faa53b97ad 100644
--- a/gcc/fortran/match.c
+++ b/gcc/fortran/match.c
@@ -6363,7 +6363,8 @@ select_type_set_tmp (gfc_typespec *ts)
sym = tmp->n.sym;
gfc_add_type (sym, ts, NULL);
- if (selector->ts.type == BT_CLASS && selector->attr.class_ok)
+ if (selector->ts.type == BT_CLASS && selector->attr.class_ok
+ && selector->ts.u.derived && CLASS_DATA (selector))
{
sym->attr.pointer
= CLASS_DATA (selector)->attr.class_pointer;
diff --git a/gcc/fortran/primary.c b/gcc/fortran/primary.c
index d873264a08e3..1f63028d1798 100644
--- a/gcc/fortran/primary.c
+++ b/gcc/fortran/primary.c
@@ -2151,6 +2151,7 @@ gfc_match_varspec (gfc_expr *primary, int equiv_flag, bool sub_flag,
&& !(gfc_matching_procptr_assignment
&& sym->attr.flavor == FL_PROCEDURE))
|| (sym->ts.type == BT_CLASS && sym->attr.class_ok
+ && sym->ts.u.derived && CLASS_DATA (sym)
&& (CLASS_DATA (sym)->attr.dimension
|| CLASS_DATA (sym)->attr.codimension)))
{
diff --git a/gcc/fortran/resolve.c b/gcc/fortran/resolve.c
index bff1b35446f5..591e81860071 100644
--- a/gcc/fortran/resolve.c
+++ b/gcc/fortran/resolve.c
@@ -5736,6 +5736,8 @@ resolve_variable (gfc_expr *e)
can't be translated that way. */
if (sym->assoc && e->rank == 0 && e->ref && sym->ts.type == BT_CLASS
&& sym->assoc->target && sym->assoc->target->ts.type == BT_CLASS
+ && sym->assoc->target->ts.u.derived
+ && CLASS_DATA (sym->assoc->target)
&& CLASS_DATA (sym->assoc->target)->as)
{
gfc_ref *ref = e->ref;
@@ -5799,7 +5801,8 @@ resolve_variable (gfc_expr *e)
/* Like above, but for class types, where the checking whether an array
ref is present is more complicated. Furthermore make sure not to add
the full array ref to _vptr or _len refs. */
- if (sym->assoc && sym->ts.type == BT_CLASS
+ if (sym->assoc && sym->ts.type == BT_CLASS && sym->ts.u.derived
+ && CLASS_DATA (sym)
&& CLASS_DATA (sym)->attr.dimension
&& (e->ts.type != BT_DERIVED || !e->ts.u.derived->attr.vtype))
{
@@ -9432,6 +9435,7 @@ resolve_select_type (gfc_code *code, gfc_namespace *old_ns)
/* Check F03:C815. */
if ((c->ts.type == BT_DERIVED || c->ts.type == BT_CLASS)
+ && selector_type
&& !selector_type->attr.unlimited_polymorphic
&& !gfc_type_is_extensible (c->ts.u.derived))
{
@@ -9442,7 +9446,8 @@ resolve_select_type (gfc_code *code, gfc_namespace *old_ns)
}
/* Check F03:C816. */
- if (c->ts.type != BT_UNKNOWN && !selector_type->attr.unlimited_polymorphic
+ if (c->ts.type != BT_UNKNOWN
+ && selector_type && !selector_type->attr.unlimited_polymorphic
&& ((c->ts.type != BT_DERIVED && c->ts.type != BT_CLASS)
|| !gfc_type_is_extension_of (selector_type, c->ts.u.derived)))
{
diff --git a/gcc/testsuite/gfortran.dg/pr102332.f90 b/gcc/testsuite/gfortran.dg/pr102332.f90
new file mode 100644
index 000000000000..f95570940834
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr102332.f90
@@ -0,0 +1,69 @@
+! { dg-do compile }
+! PR fortran/102332 - ICE in select_type_set_tmp
+! Contributed by G.Steinmetz
+
+program p
+ type t
+ real :: a, b
+ end type
+ class(t), allocatable :: x ! Valid
+ select type (y => x)
+ type is (t)
+ y%a = 0
+ end select
+end
+
+subroutine s0 (x)
+ type t
+ real :: a, b
+ end type
+ class(t) :: x ! Valid
+ select type (y => x)
+ type is (t)
+ y%a = 0
+ end select
+end
+
+subroutine s1
+ type t
+ real :: a, b
+ end type
+ class(t) :: x ! { dg-error "must be dummy, allocatable or pointer" }
+ select type (y => x)
+ type is (t)
+ y%a = 0
+ end select
+end
+
+subroutine s3
+ type t
+ real :: a, b
+ end type
+ class(t) :: x ! { dg-error "must be dummy, allocatable or pointer" }
+ select type (y => x)
+ class is (t)
+ y%a = 0
+ end select
+end
+
+subroutine s2
+ type t
+ real :: a, b
+ end type
+ class(t) :: x ! { dg-error "must be dummy, allocatable or pointer" }
+ select type (y => x)
+ type default ! { dg-error "Expected" }
+ y%a = 0
+ end select
+end
+
+subroutine s4
+ type t
+ real :: a, b
+ end type
+ class(t) :: x ! { dg-error "must be dummy, allocatable or pointer" }
+ select type (y => x)
+ class default
+ y%a = 0
+ end select
+end
--
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