diff options
| author | Stefano Lattarini <stefano.lattarini@gmail.com> | 2012-11-03 13:05:09 +0100 |
|---|---|---|
| committer | Eric Blake <eblake@redhat.com> | 2012-11-09 16:16:22 -0700 |
| commit | 1ed0548896e941b381e96724e41badc42ef7ec6e (patch) | |
| tree | fee14cc6bd4837e7974a747d2d23fbe2638d89f9 /lib/m4sugar | |
| parent | 4f6345bda73fc081a57f4e733512cd946aeeb3fd (diff) | |
| download | autoconf-1ed0548896e941b381e96724e41badc42ef7ec6e.tar.gz | |
warn: allow aclocal to silence m4_require warnings
We introduce a new witness macro, m4_require_silent_probe, for use by
aclocal during the Autoconf-without-aclocal-m4 language. This will let
aclocal process AC_CONFIG_MACRO_DIRS without emitting spurious warnings.
In fact, if aclocal doesn't suppress require warnings, then, when some macro
expanded in configure.ac calls AC_REQUIRE on another macro that is defined
in one of the local m4 macro dirs specified with AC_CONFIG_MACRO_DIRS, the
*first* autom4te invocation issued by aclocal, not yet being able to "see"
the m4 macro definitions in the local m4 dirs, will print spurious
warnings like:
configure.ac:4: warning: MY_BAR is m4_require'd but not m4_defun'd
configure.ac:3: MY_FOO is expanded from...
Expose the use of this macro in our testsuite.
Originally reported by Nick Bowler; see point (4) of:
<http://lists.gnu.org/archive/html/autoconf-patches/2012-11/msg00000.html>
* lib/m4sugar/m4sugar.m4 (_m4_require_call): Make warnings in the
-Wsyntax category depend on the witness macro.
* tests/m4sugar.at (m4@&t@_require: warning message): New test.
* doc/autoconf.texi (Prerequisite Macros): Document how aclocal
can silence AC_REQUIRE (m4_require) warnings.
Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Diffstat (limited to 'lib/m4sugar')
| -rw-r--r-- | lib/m4sugar/m4sugar.m4 | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/lib/m4sugar/m4sugar.m4 b/lib/m4sugar/m4sugar.m4 index 12a9ab74..94c4ba86 100644 --- a/lib/m4sugar/m4sugar.m4 +++ b/lib/m4sugar/m4sugar.m4 @@ -2080,13 +2080,19 @@ m4_if([$0], [m4_require], [[m4_defun]], [[AC_DEFUN]])['d macro])])]dnl # # This is called frequently, so minimize the number of macro invocations # by avoiding dnl and other overhead on the common path. +# The use of a witness macro protecting the warning allows aclocal +# to silence any warnings when probing for what macros are required +# and must therefore be located, when using the Autoconf-without-aclocal-m4 +# autom4te language. For more background, see: +# https://lists.gnu.org/archive/html/automake-patches/2012-11/msg00035.html m4_define([_m4_require_call], [m4_pushdef([_m4_divert_grow], m4_decr(_m4_divert_grow))]dnl [m4_pushdef([_m4_diverting([$1])])m4_pushdef([_m4_diverting], [$1])]dnl [m4_divert_push(_m4_divert_grow, [-])]dnl [m4_if([$2], [], [$1], [$2]) m4_provide_if([$1], [m4_set_remove([_m4_provide], [$1])], - [m4_warn([syntax], [$1 is m4_require'd but not m4_defun'd])])]dnl + [m4_ifndef([m4_require_silent_probe], + [m4_warn([syntax], [$1 is m4_require'd but not m4_defun'd])])])]dnl [_m4_divert_raw($3)_m4_undivert(_m4_divert_grow)]dnl [m4_divert_pop(_m4_divert_grow)_m4_popdef([_m4_divert_grow], [_m4_diverting([$1])], [_m4_diverting])]) |