On Linux/ia32, revision 161747 gave ERROR: couldn't compile regular expression pattern: parentheses () not balanced ERROR: tcl error sourcing /export/gnu/import/svn/gcc-test/src-trunk/gcc/testsuite/gfortran.dg/dg.exp. Revision 161734 is OK.
It is caused by revision 161745: http://gcc.gnu.org/ml/gcc-cvs/2010-07/msg00098.html
gfortran.dg/char_bounds_check_fail_1.f90 is the problem.
Fixed by revision 161767: http://gcc.gnu.org/ml/gcc-cvs/2010-07/msg00120.html