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| author | Tom Tromey <tromey@adacore.com> | 2023-01-11 12:42:40 -0700 |
|---|---|---|
| committer | Tom Tromey <tromey@adacore.com> | 2023-02-09 07:55:34 -0700 |
| commit | 1775f8b3804744c22611ed0c9fd2df4f5b4d8641 (patch) | |
| tree | 06c240bfc9fe68afe224cfc4e9bddc3e09e7850b /gdb/testsuite/gdb.dwarf2 | |
| parent | 119f6cfbd0236c9684a8a12ff9241dc834418309 (diff) | |
| download | gdb-1775f8b3804744c22611ed0c9fd2df4f5b4d8641.zip gdb-1775f8b3804744c22611ed0c9fd2df4f5b4d8641.tar.gz gdb-1775f8b3804744c22611ed0c9fd2df4f5b4d8641.tar.bz2 | |
Increase size of main_type::nfields
main_type::nfields is a 'short', and has been for many years. PR
c++/29985 points out that 'short' is too narrow for an enum that
contains more than 2^15 constants.
This patch bumps the size of 'nfields'. To verify that the field
isn't directly used, it is also renamed. Note that this does not
affect the size of main_type on x86-64 Fedora 36. And, if it does
have a negative effect somewhere, it's worth considering that types
could be shrunk more drastically by using subclasses for the different
codes.
This is v2 of this patch, which has these changes:
* I changed nfields to 'unsigned', per Simon's request. I looked at
changing all the uses, but this quickly fans out into a very large
patch. (One additional tweak was needed, though.)
* I wrote a test case. I discovered that GCC cannot compile a large
enough C test case, so I resorted to using the DWARF assembler.
This test doesn't reproduce the crash, but it does fail without the
patch.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29985
Diffstat (limited to 'gdb/testsuite/gdb.dwarf2')
| -rw-r--r-- | gdb/testsuite/gdb.dwarf2/mega-enum.exp | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/gdb/testsuite/gdb.dwarf2/mega-enum.exp b/gdb/testsuite/gdb.dwarf2/mega-enum.exp new file mode 100644 index 0000000..9d47931 --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/mega-enum.exp @@ -0,0 +1,67 @@ +# Copyright 2023 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 3 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, see <http://www.gnu.org/licenses/>. + +# Test a huge enum. A colossal enum. If you will, a mega enum. + +load_lib dwarf.exp +require dwarf2_support + +standard_testfile main.c mega-enum.S + +set asm_file [standard_output_file $srcfile2] +Dwarf::assemble $asm_file { + global srcfile + + cu {} { + DW_TAG_compile_unit { + {DW_AT_language @DW_LANG_C} + {DW_AT_name $srcfile} + {DW_AT_comp_dir /tmp} + } { + declare_labels integer_label + + integer_label: DW_TAG_base_type { + {DW_AT_byte_size 4 DW_FORM_sdata} + {DW_AT_encoding @DW_ATE_signed} + {DW_AT_name int} + } + + DW_TAG_enumeration_type { + {DW_AT_name mega_enum} + {DW_AT_type :$integer_label} + } { + # In the past gdb used a 'short' for the field count. + # But this fails if there are too many fields. If the + # field count here is too high, gas takes a long time; + # so use a number that's just big enough. + for {set i 0} {$i < 65538} {incr i} { + DW_TAG_enumerator { + {DW_AT_name DEI_$i} + {DW_AT_const_value $i DW_FORM_sdata} + } + } + } + } + } +} + +if {[prepare_for_testing "failed to prepare" ${testfile} \ + [list $srcfile $asm_file] {nodebug}]} { + return -1 +} + +# The largest known Fermat prime. +gdb_test "print/d DEI_65537" " = 65537" +gdb_test "print (enum mega_enum) 65537" " = DEI_65537" |