gdb/testsuite/gdb.base/vla-optimized-out.exp

   1 # Copyright 2018-2020 Free Software Foundation, Inc.
   2
   3 # This program is free software; you can redistribute it and/or modify
   4 # it under the terms of the GNU General Public License as published by
   5 # the Free Software Foundation; either version 3 of the License, or
   6 # (at your option) any later version.
   7 #
   8 # This program is distributed in the hope that it will be useful,
   9 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 # GNU General Public License for more details.
  12 #
  13 # You should have received a copy of the GNU General Public License
  14 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15
  16 # Check whether we can determine the size of an optimized-out vla.
  17
  18 standard_testfile
  19
  20 # The EXE_SUFFIX is a string appended to the name of the test binary
  21 # to make it unique per variation.
  22 # The OPTIONS is a two item list, the first item is a list of compiler
  23 # flags used for building the test binary, and the second item is a
  24 # pattern which matches some expected output within this proc.
  25 proc vla_optimized_out {exe_suffix options} {
  26     global testfile srcfile
  27
  28     lassign $options compile_flags sizeof_result
  29
  30     if { [prepare_for_testing "failed to prepare" "$testfile-$exe_suffix" $srcfile \
  31               $compile_flags] } {
  32         return -1
  33     }
  34
  35     if ![runto f1] {
  36         fail "can't run to f1"
  37         return
  38     }
  39
  40     gdb_test "p a" \
  41         " = <optimized out>" \
  42         "printed optimized out vla"
  43
  44     gdb_test "p sizeof (a)" \
  45         " = $sizeof_result" \
  46         "printed size of optimized out vla"
  47
  48     # At lower optimisation levels, the upper bound of the array is
  49     # still defined, it's just the loctaion that tells GDB the array
  50     # is optimised out.  In that case, when we access an element that
  51     # is within the bounds of the array an answer of '<optimized out>'
  52     # is reasonable.
  53     #
  54     # At higher optimisation levels, the array bounds themselves have
  55     # been removed.  As such GDB can't be expected to know if the
  56     # array contains _any_ elements at all.  It seems reasonable in
  57     # that case to reply with 'no such vector element'.
  58     gdb_test "p a\[0\]" \
  59         "(= <optimized out>|no such vector element)" \
  60         "print out of range element of vla (0)"
  61
  62     gdb_test "p a\[6\]" \
  63         "no such vector element" \
  64         "print out of range element of vla (6)"
  65
  66     gdb_test "p a\[0xffffffff\]" \
  67         "no such vector element" \
  68         "print out of range element of vla (0xffffffff)"
  69 }
  70
  71 foreach {test_prefix options} \
  72     { "o1" {{debug optimize=-O1 additional_flags=-DNOCLONE} "6"} \
  73       "o3" {{debug optimize=-O3} "<optimized out>|6"} \
  74       "o3_strict" {{debug optimize=-O3 \
  75                         additional_flags=-gstrict-dwarf} \
  76                        "<optimized out>|6"}} {
  77     with_test_prefix $test_prefix {
  78         vla_optimized_out $test_prefix $options
  79     }
  80 }
  81