Daniel Gustafsson <dan...@yesql.se> writes: > On 10 Mar 2020, at 18:38, Peter Eisentraut <peter.eisentr...@2ndquadrant.com> > wrote: >> Btw., here is an older thread for the same issue >> <https://www.postgresql.org/message-id/flat/1358164265.29612.7.camel%40vanquo.pezone.net>. >> Might be worth reflecting on the issues discussed there.
> Thanks, didn't realize that the subject had been up for discussion earlier as > well. > For me, the duplication aspect is the most troubling, since we'd still need > the > xml2-config fallback and thus won't be able to simplify the code. Yeah, but at least it's concentrated in a few lines in configure.in. I think that the main objection to this is the documentation/confusion issues raised by Noah in that old thread. Still, we probably don't have much choice given that some distros are going to remove xml2-config. In that connection, Hugh's patch lacks docs which is entirely not OK, but the doc changes in Peter's old patch look workable. I wonder whether we ought to try to align this with our documented procedure for falling back if you have no icu-config but want to use ICU; that part of the docs suggests setting ICU_CFLAGS and ICU_LIBS manually. The patch as it stands doesn't seem to support manually giving XML2_CFLAGS and XML2_LIBS, but it looks like it could easily be adjusted to allow that. Also, I see that pkg.m4 says dnl Note that if there is a possibility the first call to dnl PKG_CHECK_MODULES might not happen, you should be sure to include an dnl explicit call to PKG_PROG_PKG_CONFIG in your configure.ac which we are not doing. We got away with that as long as there was only one PKG_CHECK_MODULES call ... but with two, I'd expect that the second one will fall over if the first one isn't executed. regards, tom lane