assembly - Faulty compilation of string constant in ASM -


i'm writing program hashes of function-names in asm.

the function fetch string constants following:

get_strings:     call get_curr_addr     pop esi     add esi, 9     jmp str_return        db "loadlibrarya"     db 0x00

this produces following string constant in bytecode (xxd output):

 ...     00000040: 2424 61c3 e8bc ffff ff5e 83c6 09eb 7d4c  $$a......^....}l     00000050: 6f61 644c 6962 7261 7279 4100 .... ....  oadlibrarya.

ollydbg interprets as:

ascii "dlibrarya",0

when change code following:

get_strings:     call get_curr_addr     pop esi     add esi, 9     jmp str_return        db "jibberish"     db 0x00      db "loadlibrarya"     db 0x00

the compilation done "right" (the way expect be).

xxd output:

... 00000050: 0000 4a69 6262 6572 6973 6800 4c6f 6164  ..jibberish.load 00000060: 4c69 6272 6172 7941 00.. .... .... ....  librarya.

and there's no 

7d
byte anymore in front of loadlibrarya string literal.

ofcourse debugger sees strings should be

 ascii "jibberish",0 ascii "loadlibrarya",0

is cygwin nasm compiler that's acting weird or growing mad?

as pointed out lurker , michael in comments:

there no problem apart fact debugger attempts interpret "loa" part of "loadlibrarya" actual instruction because i've put string literals in .text (code) section.

in second example, not reproduce "jib" in "jibberish" string, can't translated instruction.

issue resolved putting literals in .data section (where belong).

in code, snippet:

get_strings:     call get_curr_addr     pop esi     add esi, 9     jmp str_return        db "loadlibrarya"     db 0x00

now becomes:

get_strings:     call get_curr_addr     pop esi     add esi, 9     jmp str_return  [section .data]     db "loadlibrarya"     db 0x00

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