Question

I have some NASM files which have a line:

%INCLUDE "bmdev.asm"

The bmdev.asm file has equ directives such as:

b_print_newline         equ 0x0000000000100040

The files which include bmdev.asm then are able to call those items. I.e.

call b_print_newline

Is there a way to convert this to GAS? When I try to do the direct translation, i.e.

.set b_print_newline , 0x100040

call b_print_string

it doesn’t appear to disassemble to the right thing:

callq  *0x100040

The NASM call disassembles to:

callq  0xfffffffffff00040

The goal here is to generate binaries for BareMetal OS via GAS instead of NASM.

The full disassembly of the binary which works:

$ objdump -D -b binary -m i386:x86-64 test-nl.app 

test-nl.app:     file format binary


Disassembly of section .data:

0000000000000000 <.data>:
   0:   e8 3b 00 f0 ff          callq  0xfffffffffff00040
   5:   c3                      retq   

The full disassembly of the binary which doesn’t work:

$ objdump -D -b binary -m i386:x86-64 test-nl-a.app 

test-nl-a.app:     file format binary


Disassembly of section .data:

0000000000000000 <.data>:
   0:   ff 14 25 40 00 10 00    callq  *0x100040
   7:   c3                      retq   

I’ve posted a (hopefully) clearer version of this question. Closing this one.

Answer 1

I brought this issue up on the binutils mailing list. It appears to be a bug. It was suggested that I file a bug report and I’ve done so.

A fix has been checked in to the binutils tree.