From d9c460b84e6dd603d0101369ee3d6f935213827c Mon Sep 17 00:00:00 2001
From: Sergei Golubchik <serg@mariadb.org>
Date: Sun, 21 Jan 2018 15:08:33 +0100
Subject: [PATCH] Finally! Make './mtr --valgrind-mysqld --gdb' to work.

It has its limitations, e.g. it assumes that there's only one
gdb and only one valgrind process is running. And a hard-coded
one-second delay might be too short for slow machines.

Still, it's better than "doesn't work at all"
---
 mysql-test/lib/My/SafeProcess.pm |  2 +-
 mysql-test/mysql-test-run.pl     | 17 +++++++++++++----
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/mysql-test/lib/My/SafeProcess.pm b/mysql-test/lib/My/SafeProcess.pm
index e7917f8fb16..7059ceebdad 100644
--- a/mysql-test/lib/My/SafeProcess.pm
+++ b/mysql-test/lib/My/SafeProcess.pm
@@ -84,7 +84,7 @@ sub is_child {
 }
 
 
-my @safe_process_cmd;
+our @safe_process_cmd;
 my $safe_kill;
 my $bindir;
 
diff --git a/mysql-test/mysql-test-run.pl b/mysql-test/mysql-test-run.pl
index 37e5d486988..61ad87cc21c 100755
--- a/mysql-test/mysql-test-run.pl
+++ b/mysql-test/mysql-test-run.pl
@@ -5378,7 +5378,7 @@ sub mysqld_start ($$) {
   my $args;
   mtr_init_args(\$args);
 
-  if ( $opt_valgrind_mysqld )
+  if ( $opt_valgrind_mysqld and not $opt_gdb and not $opt_manual_gdb )
   {
     valgrind_arguments($args, \$exe);
   }
@@ -5981,11 +5981,20 @@ sub gdb_arguments {
   unlink($gdb_init_file);
 
   # Put $args into a single string
-  my $str= join(" ", @$$args);
   $input = $input ? "< $input" : "";
 
-  # write init file for mysqld or client
-  mtr_tofile($gdb_init_file, "set args $str $input\n");
+  if ($type ne 'client' and $opt_valgrind_mysqld) {
+    my $v = $$exe;
+    my $vargs = [];
+    valgrind_arguments($vargs, \$v);
+    mtr_tofile($gdb_init_file, <<EOF);
+shell @My::SafeProcess::safe_process_cmd --parent-pid=`pgrep -x gdb` -- $v --vgdb-error=0 @$vargs @$$args &
+shell sleep 1
+target remote | /usr/lib64/valgrind/../../bin/vgdb
+EOF
+  } else {
+    mtr_tofile($gdb_init_file, "set args @$$args $input\n");
+  }
 
   if ( $opt_manual_gdb )
   {