[PATCH] Add missing null pointer check in get_sal_arch

[PATCH] Add missing null pointer check in get_sal_arch

[Craig Blackmore]

This fixes a GDB crash when trying to set a breakpoint on a function in
an ELF where there is both no .text section and the first section within
the ELF is not allocatable.

Co-authored-by: Simon Cook <simon.cook@embecosm.com>
---
 gdb/breakpoint.c                        |  2 +-
 gdb/testsuite/gdb.base/bp-non-alloc.c   | 21 +++++++++++++++
 gdb/testsuite/gdb.base/bp-non-alloc.exp | 36 +++++++++++++++++++++++++
 gdb/testsuite/gdb.base/bp-non-alloc.ld  | 35 ++++++++++++++++++++++++
 4 files changed, 93 insertions(+), 1 deletion(-)
 create mode 100644 gdb/testsuite/gdb.base/bp-non-alloc.c
 create mode 100644 gdb/testsuite/gdb.base/bp-non-alloc.exp
 create mode 100644 gdb/testsuite/gdb.base/bp-non-alloc.ld

diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index ca600a845e5..7df63856278 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -7764,7 +7764,7 @@ set_breakpoint_location_function (struct bp_location *loc)
 struct gdbarch *
 get_sal_arch (struct symtab_and_line sal)
 {
-  if (sal.section != nullptr)
+  if (sal.section != nullptr && sal.section->objfile != nullptr)
     return sal.section->objfile->arch ();
   if (sal.symtab != nullptr)
     return sal.symtab->compunit ().objfile ()->arch ();
diff --git a/gdb/testsuite/gdb.base/bp-non-alloc.c b/gdb/testsuite/gdb.base/bp-non-alloc.c
new file mode 100644
index 00000000000..2eb9f523887
--- /dev/null
+++ b/gdb/testsuite/gdb.base/bp-non-alloc.c
@@ -0,0 +1,21 @@
+/* Copyright (C) 2026 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   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/>.  */
+
+int main ()
+{
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.base/bp-non-alloc.exp b/gdb/testsuite/gdb.base/bp-non-alloc.exp
new file mode 100644
index 00000000000..7758a591fa7
--- /dev/null
+++ b/gdb/testsuite/gdb.base/bp-non-alloc.exp
@@ -0,0 +1,36 @@
+# Copyright (C) 2026 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/>.
+
+# For an ELF that has no section called ".text" and the first section is
+# non-alloc, test that a breakpoint can be set on a function.  This previously
+# caused GDB to crash due to a missing null pointer check.
+
+require is_elf_target
+
+global srcdir
+global subdir
+
+standard_testfile
+
+set linker_script $srcdir/$subdir/$testfile.ld
+
+set options "debug ldscript=-Wl,-T${linker_script}"
+if {[build_executable "failed to prepare" $testfile $srcfile $options]} {
+    return -1
+}
+
+clean_restart $testfile
+
+gdb_test "break main" "Breakpoint .* at .*"
diff --git a/gdb/testsuite/gdb.base/bp-non-alloc.ld b/gdb/testsuite/gdb.base/bp-non-alloc.ld
new file mode 100644
index 00000000000..6a8ad57af18
--- /dev/null
+++ b/gdb/testsuite/gdb.base/bp-non-alloc.ld
@@ -0,0 +1,35 @@
+/* Copyright (C) 2026 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   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 linker script is used to produce an executable that starts with a
+   non-allocatable section and does not contain a `.text` section.  */
+
+MEMORY
+{
+  DATA (rw) : ORIGIN = 0x8000000, LENGTH = 0x10000
+  TEXT (rx) : ORIGIN = LENGTH (DATA), LENGTH = 0x10000
+}
+
+SECTIONS
+{
+  .my_non_alloc_sec (INFO) : { . = . + 0x10; }
+  .text.all : { *(.text) } > TEXT
+  .data : { *(.data) } > DATA
+  _edata = .;
+  .bss : { *(.bss) } > DATA
+  _end = .;
+}
-- 
2.43.0