off-trunk gdb.fortran/dwarf-stride.exp no longer PASSes [Re: [PATCH 0/2] fort_dyn_array: Enable basic Fortran dynamic array support]

[Jan Kratochvil]

[ Now with the testfile. ]
On Tue, 27 Oct 2015 22:28:31 +0100, Jan Kratochvil wrote:

Hello,

this is not a regression for FSF GDB; but at least these Fedora versions
	gdb-7.8.2-39.fc21.x86_64
	gdb-7.9.1-17.fc22.x86_64
	gdb-7.10-29.fc24.x86_64
PASS the attached testcase
	p c40pt(1)^M
	$1 = '0-hello', ' ' <repeats 33 times>^M
	(gdb) PASS: gdb.fortran/dwarf-stride.exp: p c40pt(1)
	p c40pt(2)^M
	$2 = '1-hello', ' ' <repeats 33 times>^M
	(gdb) PASS: gdb.fortran/dwarf-stride.exp: p c40pt(2)
while current FSF trunk b80c3053162ec5533e120ee4e4ed30296d4c5fb2 FAILs on:
	p c40pt(1)^M
	$1 = '0-hello', ' ' <repeats 33 times>^M
	(gdb) PASS: gdb.fortran/dwarf-stride.exp: p c40pt(1)
	p c40pt(2)^M
	$2 = '\001\000\000\000\061-hello', ' ' <repeats 29 times>^M
	(gdb) FAIL: gdb.fortran/dwarf-stride.exp: p c40pt(2)

Curiously the Fedora GDB versions are based on:
	[PATCH 00/23] Fortran dynamic array support
	https://sourceware.org/ml/gdb-patches/2014-06/msg00108.html
	https://github.com/intel-gdb/vla/tree/vla-fortran
	commit 511bff520372ffc10fa2ff569c176bdf1e6e475d
	(although I cannot find that commit hash in that github repo now)

Couldn't the Intel patchset regress this testcase during its upstreaming?

I haven't yet tried to really fix/debug it.


Thanks,
Jan
-------------- next part --------------
diff --git a/gdb/testsuite/gdb.fortran/dwarf-stride.exp b/gdb/testsuite/gdb.fortran/dwarf-stride.exp
new file mode 100644
index 0000000..d7b8bea
--- /dev/null
+++ b/gdb/testsuite/gdb.fortran/dwarf-stride.exp
@@ -0,0 +1,42 @@
+# Copyright 2009 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  
+
+# This file was written by Jan Kratochvil <jan.kratochvil@redhat.com>.
+
+# This file is part of the gdb testsuite.  Array element stride must not be
+# specified in the number of elements but in a number of bytes instead.
+# Original problem:
+# (gdb) p c40pt(1)
+# $1 = '0-hello', ' ' <repeats 33 times>
+# (gdb) p c40pt(2)
+# warning: Fortran array stride not divisible by the element size
+
+set testfile dwarf-stride
+set srcfile ${testfile}.f90
+
+if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile} {debug f90}] } {
+    return -1
+}
+
+if ![runto MAIN__] then {
+    perror "couldn't run to breakpoint MAIN__"
+    continue
+}
+
+gdb_breakpoint [gdb_get_line_number "break-here"]
+gdb_continue_to_breakpoint "break-here" ".*break-here.*"
+gdb_test "p c40pt(1)" " = '0-hello.*"
+gdb_test "p c40pt(2)" " = '1-hello.*"
diff --git a/gdb/testsuite/gdb.fortran/dwarf-stride.f90 b/gdb/testsuite/gdb.fortran/dwarf-stride.f90
new file mode 100644
index 0000000..e492b3a
--- /dev/null
+++ b/gdb/testsuite/gdb.fortran/dwarf-stride.f90
@@ -0,0 +1,40 @@
+! Copyright 2009 Free Software Foundation, Inc.
+!
+! This program is free software; you can redistribute it and/or modify
+! it under the terms of the GNU General Public License as published by
+! the Free Software Foundation; either version 2 of the License, or
+! (at your option) any later version.
+!
+! This program is distributed in the hope that it will be useful,
+! but WITHOUT ANY WARRANTY; without even the implied warranty of
+! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+! GNU General Public License for more details.
+!
+! You should have received a copy of the GNU General Public License
+! along with this program; if not, write to the Free Software
+! Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+!
+! File written by Alan Matsuoka.
+
+program repro
+
+  type small_stride
+     character*40 long_string
+     integer      small_pad
+  end type small_stride
+
+  type(small_stride), dimension (20), target :: unpleasant
+  character*40, pointer, dimension(:):: c40pt
+
+  integer i
+
+  do i = 0,19
+     unpleasant(i+1)%small_pad = i+1
+     unpleasant(i+1)%long_string = char (ichar('0') + i) // '-hello'
+  end do
+
+  c40pt => unpleasant%long_string
+
+  print *, c40pt  ! break-here
+
+end program repro