I learned from this link Why is address 0x400000 chosen as a start of text segment in x86_64 ABI? that 64-bit Linux process start address by default should be 0x400000, but on my Ubuntu, I only found my bash process starts from a very high base address (0x55971cea6000). Any one knows why? and how does dynamic…
Tag: linker
Method is both defined and undefined in a static Linux library
I’m using visual studio 2019 and compiling for ARM android. One of the twelve libraries in my solution is failing to link properly. It is showing a sizable number of class methods that are both defined and undefined. Here is one example using the command line: nm -C -g Services_Droid.a 1>Services_Dro…
Linker cannot find local shared library
I’m trying a very simple exmaple to create a shared library and link to it. The shared library is as follows: Then the source code file is just as simple: I’m then compiling that into a shared library with: All good, we get an ardgrab.so library so to test it, with the following code in teh same d…
Why does the Qemu run differ from the native run?
What did i do? I ran qemu-x86_64 -singlestep -d nochain,cpu ./dummy to dump all the registers of a dummy program after each instruction and used grep to save all the RIP values into a text file (qemu_rip_dump.txt). I then singlestepped the dummy program with ptrace and dumped the RIP values after each instruc…
what is segment 00 in my Linux executable program (64 bits)
Here is a very simple assembly program, just return 12 after executed. It can be built and executed correctly: But the size of a.out is big, it is more than 4k: I try to understand it by reading elf content: it is strange, segment 00 is aligned by 0x1000, I think it means such segment at least will occupy 409…
Running address of an application, followed by heap and stack expansions
I have an m.c: and an a.c: I compile and build these as: Then, I examine the executable, linux thus: objdump -drwxCS -Mintel linux The output of this on my Ubuntu 16.04.6 starts off with: start address 0x0000000000400540 then, later, is the init section: Finally, is the fini section: The program references th…
Linker –whole-archive option
I am using C language. I am linking static libraries with –whole-archive. Linker is arm-none-eabi-ld For example, giving the following option to the linker: But still I get linking error: Why is the linking error happening? EDIT: Full command with output: Out put of: readelf -Ws kunit.a hal.a fs.a | egr…
Is it possible to make a hardcoding with the help of the command objcopy
I’m working on Linux and I’ve just heard that there was a command objcopy, I’ve found the relative command on my x86_64 PC: x86_64-linux-gnu-objcopy. With its help, I can convert a file into an obj file: x86_64-linux-gnu-objcopy -I binary -O elf64-x86-64 custom.config custom.config.o The fil…
Why do I need to set LD_LIBRARY_PATH after installing my binary?
My application is linking to a self-compiled Qt that lies in /usr/local/lib. This works fine when I start my application in the build dir. However, after I have installed my application to /usr/local/bin/ it tries to load incompatible system Qt lib that doesn’t have required symbols and fails. Why? How …
Mixing debug and release libraries: Windows vs Linux, static vs shared
This question has been asked a few times already, but I observe that it always refers to Windows. Which makes sense, given that MSVC fails with the following error: error LNK2038: mismatch detected for ‘_ITERATOR_DEBUG_LEVEL’: value ‘0’ doesn’t match value ‘2’ in main…