vim not build with upcoming Perl 5.38

[jplesnik]

Steps to reproduce

I am preparing update to Perl 5.38 for Fedora 39. During the preparation I tried to rebuild all dependencies with it.
I found that build of vim was failing with new Perl.
For the tests I used the latest devel release Perl 5.37.11

Expected behaviour

Successful build of vim

Version of Vim

9.0 1627

Environment

Fedora 39 (rawhide)
Devel release of Perl 5.37.11

Logs and stack traces

Complete log coulg be found on <https://jplesnik.fedorapeople.org/5.38/vim-build.log>
Examples from log: 

if_perl.xs: In function 'Perl_SvTRUE_common': 
/usr/lib64/perl5/CORE/embed.h:109:49: warning: implicit declaration of function 'Perl_SvPVXtrue'; did you mean 'Perl_sv_true'? [-Wimplicit-function-declaration]
  109 | # define SvPVXtrue(a)                           Perl_SvPVXtrue(aTHX_ a)
      |                                                 ^~~~~~~~~~~~~~
if_perl.xs:724:16: note: in expansion of macro 'SvPVXtrue'
  724 |         return SvPVXtrue(sv);
      |                ^~~~~~~~~
if_perl.xs: In function 'Perl_SvTRUE':
<...>
/usr/bin/ld: /tmp/ccxXLZZi.ltrans63.ltrans.o: in function `ex_perl':
/builddir/build/BUILD/vim90/src/if_perl.xs:745: undefined reference to `Perl_SvGETMAGIC'
/usr/bin/ld: /builddir/build/BUILD/vim90/src/if_perl.xs:1108: undefined reference to `Perl_SvPV_helper'
/usr/bin/ld: /builddir/build/BUILD/vim90/src/if_perl.xs:724: undefined reference to `Perl_SvPVXtrue'
/usr/bin/ld: /tmp/ccxXLZZi.ltrans63.ltrans.o: in function `perl_to_vim.lto_priv.0':
/builddir/build/BUILD/vim90/src/if_perl.xs:1210: undefined reference to `Perl_SvPV_helper'
/usr/bin/ld: /builddir/build/BUILD/vim90/src/if_perl.xs:1323: undefined reference to `Perl_SvPV_helper'
/usr/bin/ld: /builddir/build/BUILD/vim90/src/if_perl.xs:1199: undefined reference to `Perl_SvNV'
/usr/bin/ld: /builddir/build/BUILD/vim90/src/if_perl.xs:1203: undefined reference to `Perl_SvIV'
/usr/bin/ld: /tmp/ccxXLZZi.ltrans64.ltrans.o: in function `XS_VIM_DoCommand':
/builddir/build/BUILD/vim90/src/if_perl.c:1789: undefined reference to `Perl_SvPV_helper'
/usr/bin/ld: /tmp/ccxXLZZi.ltrans64.ltrans.o: in function `ex_perldo':
/builddir/build/BUILD/vim90/src/if_perl.xs:1433: undefined reference to `Perl_SvPV_helper'

[pheiduck]

A potential workaround is to configure with --enable-perlinterp=dynamic
Arch Linux is doing this overtime:
https://gitlab.archlinux.org/archlinux/packaging/packages/vim/-/blob/main/PKGBUILD#L61

[zdohnal]

A potential workaround is to configure with --enable-perlinterp=dynamic

That's how Vim is built in Fedora. However, once in time the languages define new functions in newer release, which Vim has to fake it to make this dynamic linking working - the same thing happens time to time with Python and Ruby as well.

[zdohnal]

How to reproduce:

• configure+build+install Perl from the link in the first comment:

$ wget -O perl.tar.gz https://cpan.metacpan.org/authors/id/S/SH/SHAY/perl-5.37.11.tar.gz
$ tar -xaf perl.tar.gz && cd perl-5.37.11
$ <install make and gcc>
$ # sets the options interactively
$ sh Configure
$ make && sudo make install

• compile Vim with new Perl:

$ git clone https://github.com/vim/vim
$ cd vim
$ ./configure --enable-gui=no --with-features=Huge --enable-perlinterp=dynamic
$ make

[pheiduck]

Arch Linux has Perl 5.36.1, seems like it is no longer possible to build vim with perl starting with 5.37.

[pheiduck]

I'm not a programer and know much about perl but could this be a patch for that issue?:

 /* perl-5.34 needs Perl_SvTRUE_common; used in SvTRUE_nomg_NN */
 # if (PERL_REVISION == 5) && (PERL_VERSION >= 34)
+# define sv_true(a) Perl_sv_true(aTHX_ a)
 PERL_STATIC_INLINE bool
 Perl_SvTRUE_common(pTHX_ SV * sv, const bool sv_2bool_is_fallback)
 {
@@ -721,7 +722,7 @@ Perl_SvTRUE_common(pTHX_ SV * sv, const bool sv_2bool_is_fallback)
        return FALSE;

     if (SvPOK(sv))
-       return SvPVXtrue(sv);
+       return sv_true(av);

     if (SvIOK(sv))
        return SvIVX(sv) != 0; /* casts to bool */

[pheiduck]

I build it with my patch but there are more bugs so I am not able to fix it, maybe someone else can do it.

[pheiduck]

But here are the Links where I found the code which is missing:
Not all
'Perl_sv_true'
https://github.com/Perl/perl5/blob/blead/embed.h
`Perl_SvPV_helper'
https://github.com/Perl/perl5/blob/blead/sv.h

[pheiduck]

another potential "fixup":

diff --git a/src/if_perl.xs b/src/if_perl.xs
index c69ed9ef1..00e296882 100644
--- a/src/if_perl.xs
+++ b/src/if_perl.xs
@@ -10,6 +10,11 @@
  *             Mostly written by Sven Verdoolaege.
  */

+#if (PERL_REVISION == 5) && (PERL_VERSION >= 37)
+#pragma GCC diagnostic ignored "-Wimplicit-function-declaration"
+CFLAGS="-Wl,--unresolved-symbols=ignore-all"
+#endif
+
 #define _memory_h      /* avoid memset redeclaration */
 #define IN_PERL_FILE   /* don't include if_perl.pro from proto.h */

if_perl.c needs fixes as well

[pheiduck]

I have good news:
My Last PR fixes the errors mentioned here.
And I learned a lot about Perl today. 😄
Of course I tested it within the same setup like here.
Fedora 39 + Perl 5.37.11 and Perl 5.38.0-RC1
./configure --enable-gui=no --with-features=Huge --enable-perlinterp
also works again.

[jplesnik]

@pheiduck I tested your changes with Fedora 39 and Perl 5.38.0-RC2 and it works for me.
Thank you