Shows a harmless but puzzling effect involving atexit on linux

Here the atexit callback is invoked multiple times. This is no problem, since the callback is shared among multiple processes and so multiple callbacks ensue.

Build

Build with mulle-make or alternatively :

(
   mkdir build &&
   cd build &&
   cmake .. &&
   make
)

Run

Use ldd to trigger the misbehaviour:

LD_PRELOAD="${PWD}/build/libld-preload.so" ldd ./build/main

Output

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   linux-vdso.so.1 (0x00007ffd2b2bd000)
   /home/src/srcO/mulle-core/mulle-testallocator/research/ld-preload/build/libld-preload.so (0x00007f83853c1000)
   libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f838518c000)
   /lib64/ld-linux-x86-64.so.2 (0x00007f83853cd000)
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---

Other fun stuff to try

gdb

Run program with gdb

LD_PRELOAD="${PWD}/build/libld-preload.so" gdb build/main 

will output

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lldb

Run program with lldb

LD_PRELOAD="${PWD}/build/libld-preload.so" lldb build/main 

will output

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load
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