Re: pgsql: pg_rewind: Allow writing recovery configuration

Hi,

On 2019-09-30 17:11:09 +0000, Alvaro Herrera wrote:
> pg_rewind: Allow writing recovery configuration
>
> This is provided with a new switch --write-recovery-conf and reuses the
> pg_basebackup code.
>
> Author: Paul Guo, Jimmy Yih, Ashwin Agrawal
> Reviewed-by: Alexey Kondratov, Michaël Paquier, Álvaro Herrera
> Discussion: https://postgr.es/m/CAEET0ZEffUkXc48pg2iqARQgGRYDiiVxDu+yYek_bTwJF+q=Uw@mail.gmail.com

This currently fails on windows under mingw:
https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=jacana&dt=2019-09-30%2018%3A00%3A36

Sep 30 14:11:02 ccache x86_64-w64-mingw32-gcc -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement -Werror=vla -Wendif-labels -Wmissing-format-attribute -Wformat-security -fno-strict-aliasing -fwrapv -fexcess-precision=standard -Wno-format-truncation -g -O2 pg_rewind.o parsexlog.o xlogreader.o datapagemap.o timeline.o fetch.o file_ops.o copy_fetch.o libpq_fetch.o filemap.o win32ver.o -L../../../src/port -L../../../src/common -L../../../src/common -lpgcommon -L../../../src/port -lpgport -L../../../src/interfaces/libpq -lpq -L../../../src/fe_utils -lpgfeutils -Wl,--allow-multiple-definition -Wl,--disable-auto-import -L/c/prog/3p64/lib -L/c/prog/3p64/lib -L/c/prog/3p64/openssl-win64/lib/VC -Wl,--as-needed -lpgcommon -lpgport -lintl -lxslt -lxml2 -lz -lws2_32 -lm -lws2_32 -o pg_rewind.exe
Sep 30 14:11:02 ../../../src/fe_utils/libpgfeutils.a(recovery_gen.o): In function `GenerateRecoveryConfig':
Sep 30 14:11:02 c:/mingw/msys/1.0/home/pgrunner/bf/root/HEAD/pgsql.build/../pgsql/src/fe_utils/recovery_gen.c:33: undefined reference to `createPQExpBuffer'
Sep 30 14:11:02 c:/mingw/msys/1.0/home/pgrunner/bf/root/HEAD/pgsql.build/../pgsql/src/fe_utils/recovery_gen.c:44: undefined reference to `PQserverVersion'

I assume the issue is that the specified link order is:
LDFLAGS_INTERNAL += $(libpq_pgport) -L$(top_builddir)/src/fe_utils -lpgfeutils
but pgfeutils introduces a dependency on symbols from libpq that weren't
needed at the time libpq was linked. Therefore they aren't included
inthe resulting library.

I'll reorder them.

Greetings,

Andres Freund