binutils-gdb/gdb/testsuite/gdb.base/c-linkage-name.exp

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problem looking up some symbols when they have a linkage name This patch fixes a known failure in gdb.ada/maint_with_ada.exp (maintenance check-psymtabs). Another way to witness the same issue is by considering the following Ada declarations... type Wrapper is record A : Integer; end record; u00045 : constant Wrapper := (A => 16#060287af#); pragma Export (C, u00045, "symada__cS"); ... which declares a variable name "u00045" but with a linkage name which is "symada__cS". This variable is a record with one component, the Ada equivalent of a struct with one field in C. Trying to print that variable's value currently yields: (gdb) p /x <symada__cS> 'symada(char, signed)' has unknown type; cast it to its declared type This indicates that GDB was only able to find the minimal symbol, but not the full symbol. The expected output is: (gdb) print /x <symada__cS> $1 = (a => 0x60287af) The error message gives a hint about what's happening: We processed the symbol through gdb_demangle, which in the case of this particular symbol name, ends up matching the C++ naming scheme. As a result, the demangler transforms our symbol name into 'symada(char, signed)', thus breaking Ada lookups. This patch fixes the issue by first introducing a new language_defn attribute called la_store_sym_names_in_linkage_form_p, which is a boolean to be set to true for the few languages that do not want their symbols to have their names stored in demangled form, and false otherwise. We then use this language attribute to skip the call to gdb_demangle for all languages whose la_store_sym_names_in_linkage_form_p is true. In terms of the selection of languages for which the new attribute is set to true, the selection errs on the side of preserving the existing behavior, and only changes the behavior for the languages where we are certain storing symbol names in demangling form is not needed. It is conceivable that other languages might be in the same situation, but I not knowing in detail the symbol name enconding strategy, I decided to play it safe and let other language maintainers potentially adjust their language if it makes sense to do so. gdb/ChangeLog: PR gdb/22670 * dwarf2read.c (dwarf2_physname): Do not return the demangled symbol name if the CU's language stores symbol names in linkage format. * language.h (struct language_defn) <la_store_sym_names_in_linkage_form_p>: New field. Adjust all instances of this struct. gdb/testsuite/ChangeLog: * gdb.ada/maint_with_ada.exp: Remove PR gdb/22670 setup_kfail. * gdb.ada/notcplusplus: New testcase. * gdb.base/c-linkage-name.c: New file. * gdb.base/c-linkage-name.exp: New testcase. Tested on x86_64-linux. This also passes AdaCore's internal GDB testsuite.
2018-03-27 15:57:16 +02:00
# Copyright 2018 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/>.
# This file is part of the gdb testsuite. It is intended to test that
# gdb can correctly print arrays with indexes for each element of the
# array.
standard_testfile .c
if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
untested "failed to compile"
return -1
}
clean_restart ${binfile}
# Try to print MUNDANE, but using its linkage name.
gdb_test "print symada__cS" \
" = {a = 100829103}" \
"print symada__cS before partial symtab expansion"
# Force the symbols to be expanded for the unit that contains
# our symada__cS symbol by, e.g. inserting a breakpoint on one
# of the founction also provided by the same using.
gdb_test "break main" \
"Breakpoint $decimal at $hex: file .*$srcfile, line $decimal\\."
# Try to print MUNDANE using its linkage name again, after partial
# symtab expansion.
gdb_test "print symada__cS" \
" = {a = 100829103}" \
"print symada__cS after partial symtab expansion"