[fpc-devel] Offset and size of .note.GNU-stack section in object files

2011-01-12 Thread Joost van der Sluis 
Hi all,

When working on bug 16545, I needed some reference so I did a 'readelf
-S' on a random .o file created by fpc.

I saw that the offset of the section behind the .note.GNU-stack section
has it's offset increased by one in comparison to the offset of
the .note.GNU-stack section. But the length of this section is 0, so
there shouldn't be an increase in the offset?

Am I right, or do I miss something?

The readelf-output of avl-tree.o, note the offsets of 4ad7 and
4ad8:

There are 12 section headers, starting at offset 0x6650:

Section Headers:
  [Nr] Name  Type Address   Offset
   Size  EntSize  Flags  Link  Info  Align
  [ 0]   NULL   
        0 0 0
  [ 1] .text PROGBITS   0040
   23a0    AX   0 0 16
  [ 2] .data PROGBITS   23e0
       WA   0 0 16
  [ 3] .bss  NOBITS     23e0
   0008    WA   0 0 16
  [ 4] .data.rel PROGBITS   23e0
   06c0    WA   0 0 16
  [ 5] .debug_frame  PROGBITS   2aa0
        0 0 8
  [ 6] .symtab   SYMTAB     2aa0
   0d68  0018   711 4
  [ 7] .strtab   STRTAB     3808
   1262     0 0 1
  [ 8] .shstrtab STRTAB     4a6a
   006d     0 0 1
  [ 9] .note.GNU-stack   PROGBITS   4ad7
        0 0 1
  [10] .rela.textRELA   4ad8
   1308  0018   6 1 4
  [11] .rela.data.relRELA   5de0
   0870  0018   6 4 4
Key to Flags:
  W (write), A (alloc), X (execute), M (merge), S (strings)
  I (info), L (link order), G (group), x (unknown)
  O (extra OS processing required) o (OS specific), p (processor
specific)


 

 

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Re: [fpc-devel] Offset and size of .note.GNU-stack section in object files

2011-01-12 Thread Jonas Maebe 


On 12 Jan 2011, at 13:12, Joost van der Sluis wrote:

I saw that the offset of the section behind the .note.GNU-stack  
section

has it's offset increased by one in comparison to the offset of
the .note.GNU-stack section. But the length of this section is 0, so
there shouldn't be an increase in the offset?

Am I right, or do I miss something?


Alignment: .rela.text alignment = 4, and align(0x4ad7,4) =  
0x4ad8.



Jonas
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Re: [fpc-devel] Offset and size of .note.GNU-stack section in object files

2011-01-12 Thread Joost van der Sluis 
On Wed, 2011-01-12 at 13:22 +0100, Jonas Maebe wrote:
 On 12 Jan 2011, at 13:12, Joost van der Sluis wrote:
 
  I saw that the offset of the section behind the .note.GNU-stack  
  section
  has it's offset increased by one in comparison to the offset of
  the .note.GNU-stack section. But the length of this section is 0, so
  there shouldn't be an increase in the offset?
 
  Am I right, or do I miss something?
 
 Alignment: .rela.text alignment = 4, and align(0x4ad7,4) =  
 0x4ad8.

Offcourse, thanks. 

Joost.

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