diff --git a/gdb/dwarf2/frame.c b/gdb/dwarf2/frame.c
index 152bebef0e30..2301d9146373 100644
--- a/gdb/dwarf2/frame.c
+++ b/gdb/dwarf2/frame.c
@@ -962,6 +962,10 @@ dwarf2_frame_cache (const frame_info_ptr &this_frame, void **this_cache)
       /* Calculate the CFA.  */
       switch (fs.regs.cfa_how)
 	{
+	case CFA_UNSET:
+	  cache->undefined_retaddr = true;
+	  return cache;
+
 	case CFA_REG_OFFSET:
 	  cache->cfa = read_addr_from_reg (this_frame, fs.regs.cfa_reg);
 	  if (fs.armcc_cfa_offsets_reversed)
diff --git a/gdb/testsuite/gdb.dwarf2/debug-frame-no-cfa.exp b/gdb/testsuite/gdb.dwarf2/debug-frame-no-cfa.exp
new file mode 100644
index 000000000000..8442b5c3ddbb
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/debug-frame-no-cfa.exp
@@ -0,0 +1,54 @@
+# Copyright 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/>.
+
+# Test GDB against an FDE in the .debug_frame section that doesn't set a rule
+# for the CFA.
+
+load_lib dwarf.exp
+
+require dwarf2_support is_x86_64_m64_target
+
+standard_testfile main.c -dw.S
+
+set asm_file [standard_output_file $srcfile2]
+Dwarf::assemble $asm_file {
+    get_func_info main
+
+    frame {
+	declare_labels cie_label
+
+	cie_label: CIE {
+	    return_address_register 16
+	} {}
+
+	FDE $cie_label $main_start $main_len {} {
+	}
+    }
+}
+
+if { [prepare_for_testing "failed to prepare" ${testfile} \
+	[list $srcfile $asm_file] {nodebug}] } {
+    return
+}
+
+if { ![runto_main] } {
+    return
+}
+
+# This would cause an internal error in dwarf2_frame_cache.
+#
+# Make sure to match a single line, so that the test fails if an error
+# about stack unwind is printed after frame 0.
+gdb_test "backtrace" "^#0 \[^\r\n\]* main \[^\r\n\]*"