Re: pkg/60439: lang/gcc12 fails to build on NetBSD/macppc 11.0_RC6 but succeeds on 10.0

[Havard Eidnes <he%NetBSD.org@localhost>]

Hi,

I took a look at the executables with "objdump -x", and looking
for the sections with "CODE", for the one compiled with the
in-tree gcc, I find:

  8 .init         00000020  0180040c  0180040c  0000040c  2**2
                  CONTENTS, ALLOC, LOAD, READONLY, CODE
  9 .text         000006c0  01800430  01800430  00000430  2**4
                  CONTENTS, ALLOC, LOAD, READONLY, CODE
 10 .fini         00000020  01800af0  01800af0  00000af0  2**2
                  CONTENTS, ALLOC, LOAD, READONLY, CODE

However, for the one built by the half-built gcc12 compiler, I
additionally find:

 20 .got          00000010  01820000  01820000  00010000  2**2
                  CONTENTS, ALLOC, LOAD, CODE
 21 .sdata        00000004  01820010  01820010  00010010  2**2
                  CONTENTS, ALLOC, LOAD, DATA
 22 .sbss         00000010  01820018  01820018  00010014  2**3
                  ALLOC
 23 .plt          000000c0  01820028  01820028  00010014  2**2
                  ALLOC, CODE

and those two "CODE" marked sections are not marked as "CODE"
when using the in-tree compiler.

I've already tried linking the gcc12-built conftest.o that I
built with the system linker, and the resulting executable still
aborts, so collect2 and/or the linker does not appear to be to
blame.

Looking at the object files with "objdump -x" shows the same two
sections marked as CODE (and no others):

Sections:
Idx Name          Size      VMA       LMA       File off  Algn
  0 .text         00000000  00000000  00000000  00000034  2**0
                  CONTENTS, ALLOC, LOAD, READONLY, CODE
...
  5 .text.startup 00000068  00000000  00000000  00000050  2**2
                  CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE

and skimming through the rest reveals just one notable change:
the in-tree-built conftest.o has

RELOCATION RECORDS FOR [.text.startup]:
OFFSET   TYPE              VALUE
00000016 R_PPC_REL16_HA    .got2+0x0000800a
0000001e R_PPC_REL16_LO    .got2+0x00008012
00000028 R_PPC_PLTREL24    fopen+0x00008000
00000054 R_PPC_PLTREL24    fclose+0x00008000

whereas the gcc12-built has

RELOCATION RECORDS FOR [.text.startup]:
OFFSET   TYPE              VALUE
00000000 R_PPC_REL32       .got2+0x00007ff0
0000002c R_PPC_PLTREL24    fopen
00000058 R_PPC_PLTREL24    fclose

But I don't see how that will make such a difference in the
executables.

Any more hints for what to look for?