binutils-gdb/gdb/testsuite/gdb.base/decl-before-def-decl.c
Tom de Vries de82891ce5 [gdb/symtab] Prefer def over decl (inter-CU case)
When running test-case gdb.threads/tls.exp with target board -readnow, we
have:
...
(gdb) print a_thread_local^M
Cannot find thread-local storage for process 0, executable file tls/tls:^M
Cannot find thread-local variables on this target^M
(gdb) FAIL: gdb.threads/tls.exp: print a_thread_local
...
while with native we have:
...
(gdb) print a_thread_local^M
Cannot read `a_thread_local' without registers^M
(gdb) PASS: gdb.threads/tls.exp: print a_thread_local
...

The difference in behaviour can be explained as follows.  Without -readnow, we
have two a_thread_locals, the def and the decl, each in a different CU:
...
$ gdb -batch outputs/gdb.threads/tls/tls \
    -ex "maint expand-symtabs" \
    -ex "print a_thread_local" \
    -ex "maint print symbols" \
    | grep "a_thread_local;"
Cannot read `a_thread_local' without registers
 int a_thread_local; computed at runtime
 int a_thread_local; unresolved
...
and with -readnow, we have the opposite order:
...
$ gdb -readnow -batch outputs/gdb.threads/tls/tls  \
    -ex "maint expand-symtabs" \
    -ex "print a_thread_local" \
    -ex "maint print symbols" \
    | grep "a_thread_local;"
Cannot find thread-local storage for process 0, executable file tls/tls:
Cannot find thread-local variables on this target
 int a_thread_local; unresolved
 int a_thread_local; computed at runtime
...

Fix the FAIL by preferring the def over the decl (something we already do
intra-CU since the fix for PR24971, commit 93e55f0a03 "[gdb/symtab] Prefer var
def over decl").

Build and reg-tested on x86_64-linux.

gdb/ChangeLog:

2020-04-23  Tom de Vries  <tdevries@suse.de>

	PR symtab/25807
	* block.c (best_symbol, better_symbol): Promote to external.
	* block.h (best_symbol, better_symbol): Declare.
	* symtab.c (lookup_symbol_in_objfile_symtabs): Prefer def over
	decl.

gdb/testsuite/ChangeLog:

2020-04-23  Tom de Vries  <tdevries@suse.de>

	* gdb.base/decl-before-def-decl.c: New test.
	* gdb.base/decl-before-def-def.c: New test.
	* gdb.base/decl-before-def.exp: New file.
2020-04-23 15:42:47 +02:00

25 lines
810 B
C

/* This testcase is part of GDB, the GNU debugger.
Copyright 2020 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/>. */
extern int a[];
int
main (void)
{
a[0] = 1;
return 0;
}