diff --git a/mysql-test/lib/mtr_io.pl b/mysql-test/lib/mtr_io.pl
index 984d834486c..09749bc74e3 100644
--- a/mysql-test/lib/mtr_io.pl
+++ b/mysql-test/lib/mtr_io.pl
@@ -13,6 +13,8 @@ sub mtr_tofile ($@);
 sub mtr_tonewfile($@);
 sub mtr_lastlinefromfile($);
 sub mtr_appendfile_to_file ($$);
+sub mtr_grab_file($);
+
 
 ##############################################################################
 #
@@ -128,6 +130,7 @@ sub unspace {
   return "$quote$string$quote";
 }
 
+# Read a whole file, stripping leading and trailing whitespace.
 sub mtr_fromfile ($) {
   my $file=  shift;
 
@@ -181,5 +184,16 @@ sub mtr_appendfile_to_file ($$) {
   close TOFILE;
 }
 
+# Read a whole file verbatim.
+sub mtr_grab_file($) {
+  my $file= shift;
+  open(FILE, '<', $file)
+    or return undef;
+  local $/= undef;
+  my $data= scalar(<FILE>);
+  close FILE;
+  return $data;
+}
+
 
 1;
diff --git a/mysql-test/mysql-test-run.pl b/mysql-test/mysql-test-run.pl
index 3c855fb0499..534dbe75bcd 100755
--- a/mysql-test/mysql-test-run.pl
+++ b/mysql-test/mysql-test-run.pl
@@ -1630,9 +1630,17 @@ sub environment_setup () {
   # impossible to add correct supressions, that means if "/usr/lib/debug"
   # is available, it should be added to
   # LD_LIBRARY_PATH
+  #
+  # But pthread is broken in libc6-dbg on Debian <= 3.1 (see Debian
+  # bug 399035, http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=399035),
+  # so don't change LD_LIBRARY_PATH on that platform.
   # --------------------------------------------------------------------------
   my $debug_libraries_path= "/usr/lib/debug";
-  if (  $opt_valgrind and -d $debug_libraries_path )
+  my $deb_version;
+  if (  $opt_valgrind and -d $debug_libraries_path and
+        (! -e '/etc/debian_version' or
+         ($deb_version= mtr_grab_file('/etc/debian_version')) == 0 or
+         $deb_version > 3.1 ) )
   {
     push(@ld_library_paths, $debug_libraries_path);
   }
diff --git a/mysql-test/r/read_only.result b/mysql-test/r/read_only.result
index 1a1991a6255..69d25fbef6f 100644
--- a/mysql-test/r/read_only.result
+++ b/mysql-test/r/read_only.result
@@ -39,6 +39,11 @@ delete t1 from t1,t3 where t1.a=t3.a;
 drop table t1;
 insert into t1 values(1);
 ERROR HY000: The MySQL server is running with the --read-only option so it cannot execute this statement
+drop temporary table ttt;
+ERROR 42S02: Unknown table 'ttt'
+drop temporary table if exists ttt;
+Warnings:
+Note	1051	Unknown table 'ttt'
 drop table t1,t2;
 drop user test@localhost;
 set global read_only=0;
diff --git a/mysql-test/t/read_only.test b/mysql-test/t/read_only.test
index 175a5bba6fa..8e14b310f4c 100644
--- a/mysql-test/t/read_only.test
+++ b/mysql-test/t/read_only.test
@@ -101,6 +101,18 @@ drop table t1;
 --error 1290
 insert into t1 values(1);
 
+#
+# BUG #22077 "DROP TEMPORARY TABLE fails with wrong error if read_only is set"
+#
+# check if DROP TEMPORARY on a non-existing temporary table returns the right
+# error
+
+--error ER_BAD_TABLE_ERROR
+drop temporary table ttt;
+
+# check if DROP TEMPORARY TABLE IF EXISTS produces a warning with read_only set
+drop temporary table if exists ttt;
+
 connection default;
 drop table t1,t2;
 drop user test@localhost;
diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc
index 5b61a5fb48a..b45d15da542 100644
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -2580,10 +2580,11 @@ mysql_execute_command(THD *thd)
     if (opt_readonly &&
 	!(thd->security_ctx->master_access & SUPER_ACL) &&
 	(sql_command_flags[lex->sql_command] & CF_CHANGES_DATA) &&
-	!((lex->sql_command == SQLCOM_CREATE_TABLE) &&
-	  (lex->create_info.options & HA_LEX_CREATE_TMP_TABLE)) &&
-	((lex->sql_command != SQLCOM_UPDATE_MULTI) &&
-	 some_non_temp_table_to_be_updated(thd, all_tables)))
+        !((lex->sql_command == SQLCOM_CREATE_TABLE) &&
+          (lex->create_info.options & HA_LEX_CREATE_TMP_TABLE)) &&
+        !((lex->sql_command == SQLCOM_DROP_TABLE) && lex->drop_temporary) &&
+        ((lex->sql_command != SQLCOM_UPDATE_MULTI) &&
+          some_non_temp_table_to_be_updated(thd, all_tables)))
     {
       my_error(ER_OPTION_PREVENTS_STATEMENT, MYF(0), "--read-only");
       DBUG_RETURN(-1);