gdb: fix using clear command to delete non-user breakpoints(PR cli/7161)

The clear command shouldn't delete momentary and internal breakpoints,
nor internal breakpoints created via Python's gdb.Breakpoint.

This patch fixes this issue and adds a testcase.

Regression tested on x86_64 openSUSE Tumbleweed(VERSION_ID="20220413").

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=7161

2 files changed, 66 insertions, 1 deletions

diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index 1a227e5..ff27174 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -10921,7 +10921,8 @@ clear_command (const char *arg, int from_tty)
 	{
 	  int match = 0;
 	  /* Are we going to delete b?  */
-	  if (b->type != bp_none && !is_watchpoint (b))
+	  if (b->type != bp_none && !is_watchpoint (b)
+	      && user_breakpoint_p (b))
 	    {
 	      for (bp_location *loc : b->locations ())
 		{
diff --git a/gdb/testsuite/gdb.base/clear_non_user_bp.exp b/gdb/testsuite/gdb.base/clear_non_user_bp.exp
new file mode 100644
index 0000000..d7bb8ab
--- /dev/null
+++ b/gdb/testsuite/gdb.base/clear_non_user_bp.exp
@@ -0,0 +1,64 @@
+# Copyright 2022 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/>.
+
+# Regression test for PR gdb/7161.  Test that GDB cannot delete non-user
+# breakpoints with clear command.
+
+proc get_maint_info_bp { var } {
+    global expect_out
+    global gdb_prompt
+
+    gdb_test_multiple "maint info break $var" "find address of internal bp $var" {
+	-re ".*(0x\[0-9a-f\]+).*$gdb_prompt $" {
+	    return $expect_out(1,string)
+	}
+	timeout {
+	    perror "couldn't find address of $var"
+	    return ""
+	}
+    }
+    return ""
+}
+
+standard_testfile .c
+
+# This testcase just needs a "Hello world" source file, reuse
+# gdb.base/main.c instead of adding a new one.
+if  { [gdb_compile "${srcdir}/${subdir}/main.c" "${binfile}" executable {debug}] != "" } {
+    untested "failed to compile"
+    return -1
+}
+
+# Start with a fresh gdb.
+clean_restart ${binfile}
+
+if ![runto_main] then {
+    return 0
+}
+
+gdb_test "break main.c:21" \
+    ".*Breakpoint.* at .*" \
+    "set breakpoint"
+
+set bp_addr [get_maint_info_bp "-1"]
+
+gdb_test "maint info break -1" \
+    "-1.*shlib events.*keep y.*$bp_addr.*" \
+    "maint info breakpoint -1 error"
+
+gdb_test "clear *$bp_addr" \
+    "No breakpoint at \\*$bp_addr." \
+    "clear internal breakpoint error"
+