Strange behaviour of gas version > 2.9.*

[Konrad Rieck]

Hi,
I am absolutely unsure what strange things I experience, but it seems that
versions of Gas >= 2.9.* interpret i386 instructions differently. This 
causes an illegal instruction after executing the code. 

I have to admit that I am not working the proper way. The generated 
machine code is directly inserted into a binary and not linked using
ELF files. 

I received working code if using
GNU assembler version 2.9.1 (i386-linux), using BFD version 2.9.1.0.25

$ as -a test.s -o test.o | grep copy
  93                    .globl copy
  94                            .type    copy,@function
  95                    copy:
 141                            .size    copy,.Lfe2-copy
 448 0476 E825FCFF              call copy
 464 04a5 E8F6FBFF              call copy
 482 04d6 E8C5FBFF              call copy
 test.s:95                      .text:000000a0 copy

Unfortunaly if am using a higher version, e.g.
GNU assembler version 2.11.90.0.7 (i386-linux) using BFD version 2.11.90.0.7

$ as -a test.s -o test.o | grep copy
  93                    .globl copy
  94                            .type    copy,@function
  95                    copy:
 141                            .size    copy,.Lfe2-copy
 448 0476 E8FCFFFF              call copy
 464 04a5 E8FCFFFF              call copy
 482 04d6 E8FCFFFF              call copy
 test.s:95                      .text:000000a0 copy

"call" instructions are compiled to different assembler opcodes. Why does
the same input file causes different output using different versions of Gas?
In case this is a feature, please advice me how to omit it.

Regards,
Konrad

-- 
Konrad Rieck <address@hidden>                    
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