On 10/2/18, Vincent Lefevre <vinc...@vinc17.net> wrote: > I originally reported this bug in libtool: > > https://debbugs.gnu.org/cgi/bugreport.cgi?bug=21309 > > but this actually seems to be a bug in AC_TRY_EVAL (or another macro > it uses).
AC_TRY_EVAL is not documented in the Autoconf manual. Drilling into the Autoconf source, we find that this is intentional: # The AC_TRY_EVAL and AC_TRY_COMMAND macros are dangerous and # undocumented, and should not be used. # They may be removed or their API changed in a future release. # Autoconf itself no longer uses these two macros; they are present # only for backward compatibility with previous versions of Autoconf. # Not every shell command will work due to problems with eval # and quoting, and the rules for exactly what does work are tricky. # Worse, due to double-expansion during evaluation, arbitrary unintended # shell commands could be executed in some situations. If libtool is still using this macro, and it is causing problems, then this does seem like a bug in libtool. The solution would seem to be for libtool to stop using AC_TRY_EVAL. Cheers, Nick
