Hi Julien, * Julien Lecomte wrote on Sun, Feb 19, 2006 at 01:49:45AM CET: > > if ( ($1) || exit) >/dev/null 2>&1 && \ > ( (cd $srcdir && $1) || exit) >/dev/null 2>&1; then > > Note: the '|| exit' may seem like overkill, but I copied those two lines > from another autoconf macro. This may be to avoid a long lost documented > shell bug. All I could find was (autoconf/lib/m4sh.m4): | # _AS_UNSET_PREPARE | # ----------------- | # AS_UNSET depends upon $as_unset: compute it. | # Use MAIL to trigger a bug in Bash 2.01; | # the "|| exit" suppresses the resulting "Segmentation fault" message. | # Avoid 'if ((', as that triggers a bug in pdksh 5.2.14. | m4_defun([_AS_UNSET_PREPARE], | [# Support unset when possible. | if ( (MAIL=60; unset MAIL) || exit) >/dev/null 2>&1; then | as_unset=unset | else | as_unset=false | fi | ]) So if there is no other, yet unknown reason to add `|| exit', and you have not found a shell where both `pwd -W' and the others trigger a segfault, _and_ the segfault may be suppressed with `|| exit', then you may safely delete it. No need to add to legends. Going back to your original question: what about the much simpler approach I suggested, which would avoid all of these issues? Cheers, Ralf _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx http://lists.gnu.org/mailman/listinfo/autoconf