Re: meson PGXS compatibility

Hi,

On 2022-10-10 14:35:14 -0700, Andres Freund wrote:
> On 2022-10-05 13:07:10 -0700, Andres Freund wrote:
> > 0004: solaris: Check for -Wl,-E directly instead of checking for gnu LD
> >
> > This allows us to get rid of the nontrivial detection of with_gnu_ld,
> > simplifying meson PGXS compatibility. It's also nice to delete libtool.m4.
> >
> > I don't like the SOLARIS_EXPORT_DYNAMIC variable I invented. If somebody has
> > a better idea...
>
> A cleaner approach could be to add a LDFLAGS_BE and emit the -Wl,-E into it
> from both configure and meson, solely based on whether -Wl,-E is supported. I
> haven't verified cygwin, but on our other platforms that seems to do the right
> thing.

I think that does look better. See the attached 0003.

The attached v3 of this patch has an unchanged 0001 (CRC cflags).

For 0002, I still removed LD from Makefile.global, but instead just hardcoded
ld in the export file generation portion of the backend build - there's no
working alternative linkers, and we already hardcode a bunch of other paths in
mkldexport.

0003 is changed significantly - as proposed in the message quoted above, I
introduced LDFLAGS_EX_BE and moved the detection -Wl,-E (I used
-Wl,--export-dynamic, which we previously only used on FreeBSD) into
configure, getting rid of export_dynamic.

0004, the patch introducing PGXS compat, saw a few changes too:
- I implemented one of the FIXMEs, the correct determination of strip flags
- I moved the bulk of the pgxs compat code to src/makefiles/meson.build - imo
src/meson.build got bulked up too much with pgxs-emulation code
- some minor cleanups

Greetings,

Andres Freund