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Hello,

as far as I understand, ELF files have (up to) two independent sets of
tables describing the data:

a) the section table, with entries for .text, .data, .bss,  and some
strange ones.

b) the Program header, intended for actual program loading, only describing
memory regions needed for an executable file loader.

While playing around with my cross-toolchain, trying to verify what I
understood, I found this (see the test.dump attachment):

idx	name	   size		vma	lma	file off   alignment	

  5 .sbss         00000000  f000082c  f000082c  000008a0  2**0
                  CONTENTS
  6 .bss          00000100  f0000830  f0000830  000008a0  2**4
                  ALLOC

As I understand, the .bss should be 16 byte aligned, and is thus moved to 
virtual offset f0000830 -- f000092f (instead of f000082c -- f00009cb).

The _end symbol tells the same story:

f0000930 g     O *ABS*  00000000 _end

However, in the program header, we have:

    LOAD off    0x00000074 vaddr 0xf0000000 paddr 0xf0000000 align 2**4
         filesz 0x0000082c memsz 0x0000092c flags rwx

which tells me that the program header generating code didn't notice that .bss
was moved to satisfy its alignment restrictions.

a) do I read this wrongly?
b) if no: was this noticed (and fixed) in newer ld code?

Regards,
	Ignatios Souvatzis

P.S: Program versions:

jocelyn test !% powerpc-netbsd-as -V
GNU assembler version 2.8.1 (powerpc-netbsd), using BFD version 2.8.1
jocelyn test !% powerpc-netbsd-ld -V
GNU ld version 2.8.1 (with BFD 2.8.1)
  Supported emulations:
   elf32ppc
jocelyn test !% powerpc-netbsd-objdump -V
GNU objdump 2.8.1
jocelyn test !% powerpc-netbsd-gcc -v
Reading specs from /usr/local/lib/gcc-lib/powerpc-netbsd/egcs-2.90.27/specs
gcc version egcs-2.90.27 980315 (egcs-1.0.2 release)

Set up as a cross compiler from NetBSD/m68k.

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test:     file format elf32-powerpc
test
architecture: powerpc:common, flags 0x00000012:
EXEC_P, HAS_SYMS
start address 0xf0000000

Program Header:
    LOAD off    0x00000074 vaddr 0xf0000000 paddr 0xf0000000 align 2**4
         filesz 0x0000082c memsz 0x0000092c flags rwx

Sections:
Idx Name          Size      VMA       LMA       File off  Algn
  0 .text         00000018  f0000000  f0000000  00000074  2**2
                  CONTENTS, ALLOC, LOAD, READONLY, CODE
  1 .sdata2       00000000  f0000018  f0000018  0000008c  2**2
                  CONTENTS, ALLOC, LOAD, READONLY, DATA
  2 .data         00000800  f0000018  f0000018  0000008c  2**2
                  CONTENTS, ALLOC, LOAD, DATA
  3 .got          00000010  f0000818  f0000818  0000088c  2**2
                  CONTENTS, ALLOC, LOAD, DATA
  4 .sdata        00000004  f0000828  f0000828  0000089c  2**2
                  CONTENTS, ALLOC, LOAD, DATA
  5 .sbss         00000000  f000082c  f000082c  000008a0  2**0
                  CONTENTS
  6 .bss          00000100  f0000830  f0000830  000008a0  2**4
                  ALLOC
  7 .comment      00000035  f0000930  f0000930  000008a0  2**0
                  CONTENTS, READONLY
SYMBOL TABLE:
f0000000 l    d  .text	00000000 
f0000018 l    d  .sdata2	00000000 
f0000018 l    d  .data	00000000 
f0000818 l    d  .got	00000000 
f0000828 l    d  .sdata	00000000 
f000082c l    d  .sbss	00000000 
f0000830 l    d  .bss	00000000 
f0000930 l    d  .comment	00000000 
00000000 l    d  *ABS*	00000000 
00000000 l    d  *ABS*	00000000 
00000000 l    d  *ABS*	00000000 
00000000 l    df *ABS*	00000000 test.c
f0000000 l     O .text	00000000 gcc2_compiled.
f0000018 g     O *ABS*	00000000 _etext
f0000828 g     O .sdata	00000004 blubb
f0000000 g     F .text	00000018 test1
f000882c g     O .sdata	00000000 _SDA_BASE_
f0000018 g     O .data	00000800 bla
f0000830 g     O .bss	00000100 foo
f000082c g     O *ABS*	00000000 _edata
f0000930 g     O *ABS*	00000000 _end
f0008018 g     O .sdata2	00000000 _SDA2_BASE_



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