Hi Jeremy, On Fri, Aug 27, 2021 at 10:09:58PM +0100, Jeremy Sowden wrote: > Running autogen.sh gives the following output when it gets to > doxygen/Makefile.am: > > doxygen/Makefile.am:3: warning: shell find $(top_srcdir: non-POSIX variable name > doxygen/Makefile.am:3: (probably a GNU make extension) > > Automake doesn't understand the GNU make $(shell ...) function and tries > to interpret it as an Automake variable. The Automake people would > probably say we shouldn't do that 'cause it's not portable: > > https://www.gnu.org/software/automake/manual/automake.html#Wildcards > > However, if we accept that we are targetting GNU make, but we want to > get rid of the warning, I believe there are two ways to do so. We can > tell Automake not to warn about non-portable constructions: > > diff --git a/configure.ac b/configure.ac > index 4721eebbab1f..7cd34d079e67 100644 > --- a/configure.ac > +++ b/configure.ac > @@ -6,7 +6,7 @@ AC_CANONICAL_HOST > AC_CONFIG_MACRO_DIR([m4]) > AC_CONFIG_HEADERS([config.h]) > > -AM_INIT_AUTOMAKE([-Wall foreign subdir-objects > +AM_INIT_AUTOMAKE([-Wall -Wno-portability foreign subdir-objects > tar-pax no-dist-gzip dist-bzip2 1.6]) > m4_ifdef([AM_PROG_AR], [AM_PROG_AR]) > > On the other hand, if we want to suppress the warning for just this one > GNU-ism, we can hide it from automake: > > diff --git a/configure.ac b/configure.ac > index 4721eebbab1f..b2b54d3168ad 100644 > --- a/configure.ac > +++ b/configure.ac > @@ -56,6 +56,19 @@ AS_IF([test "x$DOXYGEN" = x], [ > with_doxygen=no > ]) > ]) > +# > +# Putting $(shell ... ) directly into the doyxgen Makefile.am confuses automake, > +# which tries to interpret it as an automake variable: > +# > +# doxygen/Makefile.am:3: warning: shell find $(top_srcdir: non-POSIX variable name > +# doxygen/Makefile.am:3: (probably a GNU make extension) > +# > +# Instead, we use autoconf to substitute it into place after automake has run. > +# > +AS_IF([test "x$with_doxygen" != no], [ > + AC_SUBST([DOC_SRCS], ['$(shell find $(top_srcdir)/src -name '"'"'*.c'"'"')']) > +]) > + > AC_OUTPUT > > echo " > diff --git a/doxygen/Makefile.am b/doxygen/Makefile.am > index f38009b24114..6ed30e21ff75 100644 > --- a/doxygen/Makefile.am > +++ b/doxygen/Makefile.am > @@ -1,6 +1,6 @@ > if HAVE_DOXYGEN > > -doc_srcs = $(shell find $(top_srcdir)/src -name '*.c') > +doc_srcs = @DOC_SRCS@ > > doxyfile.stamp: $(doc_srcs) Makefile.am > rm -rf html man > > J. Thanks for the suggestioms. I strongly prefer adding -Wno-portability to AM_INIT_AUTOMAKE. The alternative patch is longer, and IMHO less clear to follow. Also it's error-prone - consider this line: > AS_IF([test "x$with_doxygen" != no], [ The test needs to be one of the following: > [test "x$with_doxygen" != xno] > [test "$with_doxygen" != no] > [test "$with_doxygen" = yes] I'd like to get rid of the warning so will send a v3. Cheers ... Duncan.
