gdb/testsuite/gdb.base/nostdlib.exp

   1 # Copyright 2010-2025 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 standard_testfile .c
  17
  18 # If we're using a stub, breakpoints at the entry point will not trigger.
  19 # See also the comment in break-entry.exp.
  20
  21 require !use_gdb_stub
  22
  23 # default_target_compile would otherwise add "-lm" making the testcase
  24 # dependent on whether the system libraries are already prelinked.
  25 # prelink: Could not set /lib64/libm-2.11.1.so owner or mode: Operation not permitted
  26 set compile {
  27     gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable $opts
  28 }
  29
  30 foreach_with_prefix pie { "nopie" "pie" } {
  31     # OPTS and BINFILE are used by the COMPILE string (defined above)
  32     # when it is evaluated below.
  33     set opts [list debug additional_flags=-nostdlib $pie]
  34     set binfile [standard_output_file $testfile-$pie]
  35
  36     set board [target_info name]
  37     if [board_info $board exists mathlib] {
  38         set mathlib [board_info $dest mathlib]
  39         set_board_info mathlib ""
  40         set err [eval $compile]
  41         set_board_info mathlib $mathlib
  42     } else {
  43         set_board_info mathlib ""
  44         set err [eval $compile]
  45         unset_board_info mathlib
  46     }
  47     if {$err != ""} {
  48         untested "failed to compile"
  49         return -1
  50     }
  51
  52     clean_restart $binfile
  53
  54     gdb_breakpoint "*marker"
  55
  56     # Say we set a permanent breakpoint on *_start.  When setting the
  57     # breakpoint, it will resolve to _start in the exec.
  58     # After starting to run, that may stay the same, and consequently
  59     # execution will stop there.
  60     # OTOH, after starting to run, that may change to *_start in the dynamic
  61     # linker, and consequently execution will stop there.
  62     # There's currently no way to enforce one or the other (PR32748).
  63     #
  64     # Say we run into a stop in *_start in the dynamic linker.  Continuing
  65     # from this situation, the dynamic linker is reported as unloaded, which
  66     # makes the breakpoint resolve again to *_start in the exec, and
  67     # consequently execution will stop there as well.
  68     #
  69     # However, we cannot rely on this behavior either.  Reporting the dynamic
  70     # linker as unloaded is a GLIBC bug, which may get fixed eventually.
  71     #
  72     # Instead of trying to cater for all these possibilities in a controlled
  73     # fashion, make the breakpoint temporary, ensuring that there will just be
  74     # one stop.
  75     gdb_breakpoint "*_start" temporary
  76
  77     gdb_run_cmd
  78
  79     # Breakpoint 2, Stopped due to shared library event
  80     # _start () at ./gdb.base/nostdlib.c:20
  81     gdb_test "" {Temporary breakpoint [0-9]+, .*_start .*} "stop at run"
  82
  83     gdb_test "continue" {Breakpoint [0-9]+, marker .*} "continue to marker"
  84
  85     # When compiling as PIE the executable will be a dynamic
  86     # executable, the dynamic linker performs the PIE relocation.
  87     # Some versions of glibc would (possibly due to a bug) report the
  88     # dynamic linker as unmapped during startup, which places the
  89     # 'shlib event' breakpoint(s) into the PENDING state.
  90     #
  91     # At one point trying to print these internal breakpoints in a
  92     # PENDING state would crash GDB, so lets make sure that doesn't
  93     # happen now.  We don't really care about the exact output,
  94     # gdb_test will spot if running this command crashes GDB, which is
  95     # all we're really checking for.
  96     gdb_test "maint info breakpoints" ".*"
  97 }