Don't start a state restoration if it is not available.
Fortuitly discovered that $SECONDS is inherited from shell to sub-shells. Good!
1 Fixes following problem building glibc-2.3.3 with gcc-4.0:
3 checking version of i686-unknown-linux-gnu-gcc ... 4.0.0, bad
4 checking for gnumake... no
5 checking for gmake... gmake
6 checking version of gmake... 3.79.1, ok
7 checking for gnumsgfmt... no
8 checking for gmsgfmt... no
9 checking for msgfmt... msgfmt
10 checking version of msgfmt... 0.11.4, ok
11 checking for makeinfo... makeinfo
12 checking version of makeinfo... 4.3, ok
13 checking for sed... sed
14 checking version of sed... 4.0.5, ok
15 checking for autoconf... autoconf
16 checking whether autoconf works... yes
18 *** These critical programs are missing or too old: gcc
20 --- glibc-2.3.3/configure.old Mon Mar 14 12:01:10 2005
21 +++ glibc-2.3.3/configure Mon Mar 14 12:02:03 2005
23 ac_prog_version=`$CC -v 2>&1 | sed -n 's/^.*version \([egcygnustpi-]*[0-9.]*\).*$/\1/p'`
24 case $ac_prog_version in
25 '') ac_prog_version="v. ?.??, bad"; ac_verc_fail=yes;;
28 ac_prog_version="$ac_prog_version, ok"; ac_verc_fail=no;;
29 *) ac_prog_version="$ac_prog_version, bad"; ac_verc_fail=yes;;