From 14b12cba8b7def5e07a3cac5efd2be8ab49d8133 Mon Sep 17 00:00:00 2001
From: Harald Anlauf <anlauf@gmx.de>
Date: Mon, 18 Sep 2023 22:11:40 +0200
Subject: [PATCH] fortran: fix checking of CHARACTER lengths in array
constructors [PR70231]
gcc/fortran/ChangeLog:
PR fortran/70231
* trans-array.cc (trans_array_constructor): In absence of a typespec,
use string length determined by get_array_ctor_strlen() to reasonably
initialize auxiliary variable for bounds-checking.
gcc/testsuite/ChangeLog:
PR fortran/70231
* gfortran.dg/bounds_check_fail_7.f90: New test.
---
gcc/fortran/trans-array.cc | 17 ++++++++++++++++
.../gfortran.dg/bounds_check_fail_7.f90 | 20 +++++++++++++++++++
2 files changed, 37 insertions(+)
create mode 100644 gcc/testsuite/gfortran.dg/bounds_check_fail_7.f90
@@ -2852,6 +2852,23 @@ trans_array_constructor (gfc_ss * ss, locus * where)
const_string = get_array_ctor_strlen (&outer_loop->pre, c,
&ss_info->string_length);
force_new_cl = true;
+
+ /* Initialize "len" with string length for bounds checking. */
+ if ((gfc_option.rtcheck & GFC_RTCHECK_BOUNDS)
+ && !typespec_chararray_ctor
+ && ss_info->string_length)
+ {
+ gfc_se length_se;
+
+ gfc_init_se (&length_se, NULL);
+ gfc_add_modify (&length_se.pre, first_len_val,
+ fold_convert (TREE_TYPE (first_len_val),
+ ss_info->string_length));
+ ss_info->string_length = gfc_evaluate_now (ss_info->string_length,
+ &length_se.pre);
+ gfc_add_block_to_block (&outer_loop->pre, &length_se.pre);
+ gfc_add_block_to_block (&outer_loop->post, &length_se.post);
+ }
}
/* Complex character array constructors should have been taken care of
new file mode 100644
@@ -0,0 +1,20 @@
+! { dg-do run }
+! { dg-additional-options "-fcheck=bounds -g" }
+! { dg-output "At line 18 .*" }
+! { dg-shouldfail "Different CHARACTER lengths (32/0) in array constructor" }
+!
+! PR fortran/70231 - CHARACTER lengths in array constructors
+
+program p
+ implicit none
+ integer, parameter :: char_len = 32
+ integer :: l = 0
+ character(char_len) :: ch = "a"
+ character(char_len), allocatable :: ch_array(:), res1(:), res2(:)
+
+ allocate(ch_array(0))
+ res1 = [ ch_array, ch ] ! was false positive
+ print *, res1
+ res2 = [[ch_array, ch(1:l)], ch(1:l)] ! was false negative on x86
+ print *, res2
+end
--
2.35.3