Questions tagged [gcc]
GNU Compiler Collection, it includes front ends for C, C++, Objective-C, Fortran, Java, Ada, and Go, as well as libraries for these languages (libstdc++, libgcj,...).
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Inject ELF with an entierly self-contained code section that can statically call standard library functions
What I want to do
What I want to do is inject an existing ELF binary with additional code that runs before the original .text section and then transfers control back to it.
What I can already do
Now, ...
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How to traverse the GCC AST nodes?
I have looked into AST representations here http://icps.u-strasbg.fr/~pop/gcc-ast.html and I would like to know how I can programmatically access this tree/traverse the nodes of my source.c file?
...
- 115
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Prevent GCC compiler from constant folding
I have simple C Code:
int main() {
int b = 3-1;
return 0;
}
And when I objdump it after compiling with no optimization:
000000000000113d <main>:
113d: f3 0f 1e fa ...
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Why this x64 shellcode doesn't work?(segmentation fault)
I found a simple shellcode on the internet.
Then, to test this shellcode, I make the simple ret overwrite code.
test.c
#include <stdio.h>
#include <string.h>
char buf[100];
int main(void)...
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Zlib structure inside a GCC static library
I'm trying to analyze a GCC static library which is a part of a commercial software.
First, I used IDA Pro to analyze entire Lib file, but it could find only object files and was unable to disassemble ...
- 151
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Output from gcc containing all included source code?
Right now, I'm using a combination of gcc -g and the objdump -S modes to generate assembly code with debug source code interleaved. However, I'm having trouble correlating some of the functions that ...
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What change to the source code would produce an LT compare rather than an OLT compare in MIPS assembly?
I need some help reverse engineering a function in MIPS assembly. It was compiled for the PlayStation 2's EmotionEngine CPU. My goal is to produce a matching decomp of the function; it is the proof-of-...
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What hints can x86 disassembly give as to GCC/G++ compiler version and options?
I've taken an interest to disassembling binaries and attempting to recreate 1:1 source code (logic) in C and C++ compiled with GCC. I say "logic" because this question does not pertain to ...
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How to locate memory address in register $esp
000011d9 <main>:
11d9: 8d 4c 24 04 lea 0x4(%esp),%ecx
11dd: 83 e4 f0 and $0xfffffff0,%esp
11e0: ff 71 fc push -0x4(%ecx)
11e3: ...
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Is disassembly of standard gcc programs trivial, or just as difficult as video game ROMs?
I am attempting to do some reverse-engineering of ARM binaries, with the ultimate goal of reverse-engineering GBA ROMs. Of course, GBA ROMs contain a mixture of code and data, so a standard ...
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silvio packer for shared libray leads to error: "ELF load command address/offset not properly aligned"
I'm trying to implement a packer based on silvio infection. The packer works fine for ET_EXEC. However, it failed with "ELF load command address/offset not properly aligned" error for the ...
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failed to trigger packer's loader by overwritting the entry of rela.dyn on aarch64
I have implemented packer of x86_64 shared library.
Briefly, a loader is injected to a shared library, and
the rela.dyn entry is modified such that it points to the address of the loader. Once the ...
- 81
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How can I tell ld to link to a local symbol in a shared object?
Symbols in shared objects can be either local or global. This is controlled by a flag in the symbol table. If the symbol is local, ld won't resolve to it.
Reverse engineering can often be aided by ...
- 267
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How to disable relro while compilation?
My doubt is how to compile the binary without RELRO? and why it is enabling FULL-RELRO when we are not providing any flags?
This is the code.
#include <stdio.h>
#include <stdlib.h>
int ...
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Comparing the static address of the vtable of a class, to the pointer to it held by the object
I know this is compiler/ABI dependent, not necessarily standardized, etc. I've always assumed, from what I've read in several places (e.g. an answer here or the example in wikipedia), that a typical ...
