* go.test/go-test.exp (errchk): Don't backslash quote parentheses
	that are already backslash quoted.
            set index [string first "dg-error" $out_line]
            regsub -start $index -all "\(\[^\\\\]\)\}\(.\)" $out_line "\\1\\\\\[\\\}\\\\\]\\2" out_line
        }
-       if [string match "*dg-error*\(*" $out_line] {
+       if [string match "*dg-error*\\\[^\\\\\]\(*" $out_line] {
            set index [string first "dg-error" $out_line]
            regsub -start $index -all "\\\\\\\(" $out_line "\\\\\[\\\(\\\\\]" out_line
        }
-       if [string match "*dg-error*\)*\}" $out_line] {
+       if [string match "*dg-error*\\\[^\\\\\]\)*\}" $out_line] {
            set index [string first "dg-error" $out_line]
            regsub -start $index -all "\\\\\\\)\(.\)" $out_line "\\\\\[\\\)\\\\\]\\1" out_line
        }