Compilation fails since perl 5.37.4

[midenok]

From rt.cpan.org bug 150950:

The distribution does not compile anymore with newer perls, see http://matrix.cpantesters.org/?dist=Enbugger%202.016

I see errors because of undefined symbols: Perl_init_debugger, Perl_pp_nextstate, Perl_pp_dbstate

I confirm compilation errors:

# make
"/usr/bin/perl" -MExtUtils::Command::MM -e 'cp_nonempty' -- Enbugger.bs blib/arch/auto/Enbugger/Enbugger.bs 644
rm -f blib/arch/auto/Enbugger/Enbugger.so
x86_64-linux-gnu-gcc  -shared -L/usr/local/lib -fstack-protector-strong  Enbugger.o  -o blib/arch/auto/Enbugger/Enbugger.so  \
      \

/usr/bin/ld: Enbugger.o: in function `XS_Enbugger_init_debugger':
/root/.local/share/.cpan/build/Enbugger-2.016-5/Enbugger.xs:218:(.text+0x52): undefined reference to `Perl_init_debugger'
/usr/bin/ld: Enbugger.o: in function `XS_Enbugger__compile_with_dbstate':
/root/.local/share/.cpan/build/Enbugger-2.016-5/Enbugger.c:363:(.text+0x206): undefined reference to `Perl_pp_dbstate'
/usr/bin/ld: Enbugger.o: relocation R_X86_64_PC32 against undefined hidden symbol `Perl_pp_dbstate' can not be used when making a shared object
/usr/bin/ld: final link failed: bad value
collect2: error: ld returned 1 exit status
make: *** [Makefile:497: blib/arch/auto/Enbugger/Enbugger.so] Error 1

Related commits: 3a15287

[bulk88]

On Win32 Perl and therefore Unix Perl, you can get fnc ptr Perl_pp_nextstate and Perl_pp_dbstate from exported symbol PL_ppaddr which is an array of func ptrs. Perl_init_debugger is not an exported symbol, but you can hack around that, by copy pasting it with a small tweak.

void
Perl_init_debugger(pTHX)
{
    HV * const ostash = PL_curstash;
    MAGIC *mg;

    PL_curstash = (HV *)SvREFCNT_inc_simple(PL_debstash);

    Perl_init_dbargs(aTHX);
    PL_DBgv = GvREFCNT_inc(gv_fetchpvs("DB::DB", GV_ADDMULTI, SVt_PVGV));
    PL_DBline = GvREFCNT_inc(gv_fetchpvs("DB::dbline", GV_ADDMULTI, SVt_PVAV));
    PL_DBsub = GvREFCNT_inc(gv_HVadd(gv_fetchpvs("DB::sub", GV_ADDMULTI, SVt_PVHV)));
    PL_DBsingle = GvSV((gv_fetchpvs("DB::single", GV_ADDMULTI, SVt_PV)));
    if (!SvIOK(PL_DBsingle))
        sv_setiv(PL_DBsingle, 0);
    mg = sv_magicext(PL_DBsingle, NULL, PERL_MAGIC_debugvar, &PL_vtbl_debugvar, 0, 0);
    mg->mg_private = DBVARMG_SINGLE;
    SvSETMAGIC(PL_DBsingle);

    PL_DBtrace = GvSV((gv_fetchpvs("DB::trace", GV_ADDMULTI, SVt_PV)));
    if (!SvIOK(PL_DBtrace))
        sv_setiv(PL_DBtrace, 0);
    // get &PL_vtbl_debugvar from exported symbol PL_magic_vtables
    mg = sv_magicext(PL_DBtrace, NULL, PERL_MAGIC_debugvar, &PL_vtbl_debugvar, 0, 0);
    mg->mg_private = DBVARMG_TRACE;
    SvSETMAGIC(PL_DBtrace);

    PL_DBsignal = GvSV((gv_fetchpvs("DB::signal", GV_ADDMULTI, SVt_PV)));
    if (!SvIOK(PL_DBsignal))
        sv_setiv(PL_DBsignal, 0);
    // get &PL_vtbl_debugvar from exported symbol PL_magic_vtables
    mg = sv_magicext(PL_DBsignal, NULL, PERL_MAGIC_debugvar, &PL_vtbl_debugvar, 0, 0);
    mg->mg_private = DBVARMG_SIGNAL;
    SvSETMAGIC(PL_DBsignal);

    SvREFCNT_dec(PL_curstash);
    PL_curstash = ostash;
}

About Perl_init_dbargs just copy paste it, it doesn't call any non-public aka private perlapi fnc symbols.

Perl_init_dbargs(pTHX)
{
    AV *const args = PL_dbargs = GvAV(gv_AVadd((gv_fetchpvs("DB::args",
                                                            GV_ADDMULTI,
                                                            SVt_PVAV))));

    if (AvREAL(args)) {
        /* Someone has already created it.
           It might have entries, and if we just turn off AvREAL(), they will
           "leak" until global destruction.  */
        av_clear(args);
        if (SvTIED_mg((const SV *)args, PERL_MAGIC_tied))
            Perl_croak(aTHX_ "Cannot set tied @DB::args");
    }
    AvREIFY_only(PL_dbargs);
}

SEGVs on ANY perl release version except YOUR exact release that you tested with and use daily, and back compat and future compat with new P5 releases, is sketchy and YMMV. But above is your fix.

[wangvisual]

I tried the patch with Perl 5.42,0, but it failed with:
/depot/binutils-2.33.1/bin/ld: Enbugger.o: in function XS_Enbugger__compile_with_dbstate': Enbugger.c:(.text+0x191): undefined reference to Perl_pp_dbstate'
/depot/binutils-2.33.1/bin/ld: Enbugger.o: relocation R_X86_64_PC32 against undefined hidden symbol `Perl_pp_dbstate' can not be used when making a shared object
/depot/binutils-2.33.1/bin/ld: final link failed: bad value
collect2: error: ld returned 1 exit status

@bulk88 Would you please help to share the full patch including Perl_pp_dbstate?

Thanks!

[wangvisual]

vibe coding give me one patch:

Enbugger.patch