Eric Blake wrote:
> When updating m4 branch-1.6 to the latest gnulib (last done in May
> 2025, so before this patch), I'm now hitting:
>
> /usr/bin/ld: builtin.o: in function `m4_maketemp':
> /home/eblake/m4-1.6/src/builtin.c:1625:(.text+0x4128): undefined reference to
> `rpl_obstack_printf'
> /usr/bin/ld: /home/eblake/m4-1.6/src/builtin.c:1636:(.text+0x4415): undefined
> reference to `rpl_obstack_printf'
> /usr/bin/ld: debug.o: in function `trace_header':
> /home/eblake/m4-1.6/src/debug.c:327:(.text+0x1042): undefined reference to
> `rpl_obstack_printf'
> /usr/bin/ld: /home/eblake/m4-1.6/src/debug.c:329:(.text+0x1069): undefined
> reference to `rpl_obstack_printf'
> /usr/bin/ld: /home/eblake/m4-1.6/src/debug.c:330:(.text+0x1085): undefined
> reference to `rpl_obstack_printf'
> /usr/bin/ld: debug.o:/home/eblake/m4-1.6/src/debug.c:332: more undefined
> references to `rpl_obstack_printf' follow
I reproduce it.
The explanation is:
config.status has this:
S["M4_LIBOBJS"]=" asnprintf.o fopen.o printf-args.o printf-parse.o vasnprintf.o"
S["M4_libm4_LIBOBJS"]=" libm4_a-asnprintf.o libm4_a-fopen.o
libm4_a-printf-args.o libm4_a-printf-parse.o libm4_a-vasnprintf.o"
S["M4tests_LIBOBJS"]=" obstack_printf.o strerror_r.o"
S["M4tests_libm4_LIBOBJS"]=" libm4_a-obstack_printf.o libm4_a-strerror_r.o"
So, there are two uses of gnulib: once for M4, once for M4tests.
The module 'obstack-printf' exists only in the second one.
The comment in gnulib/modules/obstack-printf-posix explains part of the mess.
The other part of the mess is that
* There is only one m4/gnulib-comp.m4 file,
* It contains
AC_DEFUN([M4_INIT],
[
AC_CONFIG_LIBOBJ_DIR([tests])
So, there is really a mess going on between the lib/ and the tests/ directories.
IMO the cause of the mess is that there is no explicit 'gnulib-tool'
invocation. This branch uses the pre-2006 (more than 20 years old) way of
using Gnulib with gnulib-cache.m4 as a "memory" of the last gnulib-tool
invocation.
I would recommend to fix this like in so many GNU packages that use
an explicit gnulib-tool invocation, like in GNU sed for example.
> m4 explicitly imports both the obstack and obstack-printf-posix
> modules.
What do you mean by "explicitly"? There is no explicit gnulib-tool
invocation.
Bruno
