Index: printcmd.c =================================================================== RCS file: /cvs/src/src/gdb/printcmd.c,v retrieving revision 1.142 diff -u -p -u -r1.142 printcmd.c --- printcmd.c 5 Feb 2009 00:13:43 -0000 1.142 +++ printcmd.c 7 Feb 2009 02:31:00 -0000 @@ -43,6 +43,8 @@ #include "disasm.h" #include "dfp.h" #include "valprint.h" +#include "exceptions.h" +#include "observer.h" #ifdef TUI #include "tui/tui.h" /* For tui_active et.al. */ @@ -1395,7 +1397,7 @@ display_command (char *exp, int from_tty fmt.count = 0; } - innermost_block = 0; + innermost_block = NULL; expr = parse_expression (exp); new = (struct display *) xmalloc (sizeof (struct display)); @@ -1519,6 +1521,24 @@ do_one_display (struct display *d) if (d->enabled_p == 0) return; + if (d->exp == NULL) + { + volatile struct gdb_exception ex; + TRY_CATCH (ex, RETURN_MASK_ALL) + { + innermost_block = NULL; + d->exp = parse_expression (d->exp_string); + d->block = innermost_block; + } + if (ex.reason < 0) + { + /* Can't re-parse the expression. Disable this display item. */ + d->enabled_p = 0; + warning (_("Unable to display \"%s\": %s"), d->exp_string, ex.message); + return; + } + } + if (d->block) within_current_scope = contained_in (get_selected_block (0), d->block); else @@ -1731,6 +1751,28 @@ disable_display_command (char *args, int p++; } } + +/* display_chain items point to blocks and expressions. Some expressions + in turn may point to symbols. + Both symbols and blocks are obstack_alloc'd on objfile_stack, and are + obstack_free'd when a shared library is unloaded. + Clear pointers that are about to become dangling. + Both .exp and .block will be restored next time we need to display an item + from the newly-loaded shared library. +*/ + +static void +clear_dangling_display_expressions (struct so_list *solist) +{ + struct display *d; + + for (d = display_chain; d; d = d->next) + { + xfree (d->exp); + d->exp = NULL; + d->block = NULL; + } +} /* Print the value in stack frame FRAME of a variable specified by a @@ -2367,6 +2409,8 @@ _initialize_printcmd (void) current_display_number = -1; + observer_attach_solib_unloaded (clear_dangling_display_expressions); + add_info ("address", address_info, _("Describe where symbol SYM is stored.")); Index: solib.c =================================================================== RCS file: /cvs/src/src/gdb/solib.c,v retrieving revision 1.109 diff -u -p -u -r1.109 solib.c --- solib.c 15 Jan 2009 16:35:22 -0000 1.109 +++ solib.c 7 Feb 2009 02:31:00 -0000 @@ -908,6 +908,7 @@ clear_solib (void) { struct so_list *so = so_list_head; so_list_head = so->next; + observer_notify_solib_unloaded (so); if (so->abfd) remove_target_sections (so->abfd); free_so (so); Index: testsuite/gdb.base/solib-display-lib.c =================================================================== RCS file: testsuite/gdb.base/solib-display-lib.c diff -N testsuite/gdb.base/solib-display-lib.c --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ testsuite/gdb.base/solib-display-lib.c 7 Feb 2009 02:31:00 -0000 @@ -0,0 +1,30 @@ +/* This testcase is part of GDB, the GNU debugger. + + 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 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 . */ + +int a_global = 41; +#ifndef NO_B_GLOBAL +int b_global = 42; +#endif +int c_global = 43; + +int foo () { + return a_global + +#ifndef NO_B_GLOBAL + b_global + +#endif + c_global; +} Index: testsuite/gdb.base/solib-display-main.c =================================================================== RCS file: testsuite/gdb.base/solib-display-main.c diff -N testsuite/gdb.base/solib-display-main.c --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ testsuite/gdb.base/solib-display-main.c 7 Feb 2009 02:31:00 -0000 @@ -0,0 +1,23 @@ +/* This testcase is part of GDB, the GNU debugger. + + 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 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 . */ + +extern int foo (); + +int main () +{ + return foo (); +} Index: testsuite/gdb.base/solib-display.exp =================================================================== RCS file: testsuite/gdb.base/solib-display.exp diff -N testsuite/gdb.base/solib-display.exp --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ testsuite/gdb.base/solib-display.exp 7 Feb 2009 02:31:00 -0000 @@ -0,0 +1,82 @@ +# 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 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 . +# +# Contributed by Paul Pluzhnikov +# + +# This test case verifies that if a display is active on a variable +# which belongs in a shared library, and that shared library is +# reloaded (e.g. due to re-execution of the program), GDB will continue +# to display it (gdb-6.8 crashed under this scenario). + +# Also test that a display of variable which is currently present in +# a shared library, but disappears before re-run, doesn't cause GDB +# difficulties, and that it continues to display other variables. + +if {[skip_shlib_tests] || [is_remote target]} { + return 0 +} + +# Library file. +set libname "solib-display-lib" +set srcfile_lib ${srcdir}/${subdir}/${libname}.c +set binfile_lib ${objdir}/${subdir}/${libname}.so +set lib_flags [list debug] +# Binary file. +set testfile "solib-display-main" +set srcfile ${srcdir}/${subdir}/${testfile}.c +set binfile ${objdir}/${subdir}/${testfile} +set bin_flags [list debug shlib=${binfile_lib}] + +if [get_compiler_info ${binfile}] { + return -1 +} + +if { [gdb_compile_shlib ${srcfile_lib} ${binfile_lib} $lib_flags] != "" + || [gdb_compile ${srcfile} ${binfile} executable $bin_flags] != "" } { + untested "Could not compile $binfile_lib or $binfile." + return -1 +} + +gdb_exit +gdb_start +gdb_reinitialize_dir $srcdir/$subdir +gdb_load ${binfile} + +if ![runto_main] then { + fail "Can't run to main" + return 0 +} + +gdb_test "display a_global" +gdb_test "display b_global" +gdb_test "display c_global" +gdb_test "continue" +gdb_test "run" "3: c_global = 43\\r\\n2: b_global = 42\\r\\n1: a_global = 41" "after rerun" +gdb_test "continue" + +# Now rebuild the library without b_global +if { [gdb_compile_shlib ${srcfile_lib} ${binfile_lib} \ + "$lib_flags additional_flags=-DNO_B_GLOBAL"] != ""} { + fail "Can't rebuild $binfile_lib" +} + +gdb_test "run" "3: c_global = 43\\r\\nwarning: .*b_global.*\\r\\n1: a_global = 41" "after rebuild" + + +gdb_exit + +return 0 + +