On Tue, Sep 29, 2020 at 8:04 PM Russ Allbery <eagle@xxxxxxxxx> wrote: > > This is separate from the question of how Autoconf should handle old > configure scripts and how autoupdate should work, but while you're > manually making changes to macros anyway, you will probably be happier in > the long run if you quote all arguments and make a habit of using AS_IF > instead of open-coded shell if statements. > > # Test for C compiler __func__ support > AS_IF([test "$ac_cv_have_C__func__" != 'yes'], [ > AC_CACHE_CHECK([for C compiler __func__ support], [ac_cv_have_C__func__], > [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], > [[const char *func=__func__; > return (func != 0 ? 0 : 1); > ]])], > [ac_cv_have_C__func__='yes'], > [ac_cv_have_C__func__='no'])]) > > AS_IF([test "$ac_cv_have_C__func__" = 'yes'], [ > AC_DEFINE([HAS_C__func__],[1],[Define if C compiler supports __func__]) > ]) > ]) > > This will protect against a lot of edge cases. Very much agree. We have several reports already that the betas break old scripts with insufficient quoting and/or open-coded if statements, and all I can do about them is put dire warnings in NEWS, because autoupdate can only act on obsolete _macro names_... Also I want to point out that the AS_IF wrapping the AC_CACHE_CHECK is unnecessary: AC_CACHE_CHECK does the same thing internally. zw
