A tool to dump references in an ELF file.
This information is useful when debugging a linking issue (usually over an email) and you need to trace the unsatisfied reference back to the source code. The name of the referrer is not given by all linkers, nor all the customers would report you that.
elfref finds this information by mapping relocation records back to the symbols
(functions or data) they are supposed to modify.
This is how the elfref output will look like for a function call in
a C program:
$ elfref a.o
elfref: Input (a.o) is a 64-bit little endian ELF relocatable file.
main (addr 0x00000000)
(+0x001c)-> process_args()-4
In a nutshell, this means that the function main() refers to the function
process_args().
These instructions will get you a copy of the project up and running on your local machine for development and testing purposes.
The build was only tested on Linux (Ubuntu and Red Hat) with gcc 6.+.
Earlier versions of gcc will work, but require a minor modification
to ./Makefile to remove more recent warning options.
$ git clone https://github.com/mkartashev/elfref.git
$ cd elfref/
$ make
Issue make help for more.
Use elfref -h to get help:
Usage: elfref [OPTIONS]... ELF-FILE
find what symbols (funcs and global variables) reference in ELF-FILE
Options:
-s pattern only show info about symbols of which pattern is a substring
-f only show info about functions (symbol type FUNC);
by default, OBJECTs are also shown
-d print offsets in decimal instead of hex
-h display help
-v verbose output
-vv verbose and debug output
Output format:
sym-name (addr sym-value) <-- symbol name and address
(+offset-from-sym) -> [sym-name[()]] [+addend]
^ ^ ^
+- offset from sym | +- addend (for RELA relocations)
start +- name of referenced symbol; () means it's a function
Maxim Kartashev.
This project is released into the public domain.
See LICENSE for more details.