elf - Showing high and low PC of every program functions using DWARF library -
i trying make code work : https://github.com/eliben/code-for-blog/blob/master/2011/dwarf_get_func_addr.c extracted tutorial made eli bendersky on http://eli.thegreenplace.net/2011/02/07/how-debuggers-work-part-3-debugging-information unfortunately, low pc , high pc return same address every function:
dw_tag_subprogram: 'afunctionname' low pc : 0x00000001 high pc : 0x7f3a00000001
whereas if objdump --dwarf=decodedline ./lulesh_normal >> dump_dwarf.txt gives me :
file name line number starting address lulesh.cc 1297 0x402e00 lulesh.cc 1297 0x402e11 lulesh.cc 1299 0x402ee4 lulesh.cc 1300 0x402ef0 lulesh.cc 1301 0x402ef6 lulesh.cc 1299 0x402f00 [...]
so manages link line , address not find real address of functions. idea why ?
thank help,
the code in dwarf_get_func_addr.c
has @ least 1 bug: assumes every function has dw_at_low_pc
, dw_at_high_pc
attributes, , print uninitialized values if not case.
you should initialize lowpc = highpc = -1;
on line 42, not print unintialized values.
other that, it's impossible without access lulesh_normal
binary.
you should readelf -wi lulesh_normal
, , step through list_func_in_die
in debugger, , compare program reading there output readelf
-- should match 1 one. if don't, version of libdwarf
possibly buggy.
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