readelf: Error: Not an ELF file

[TheSunCat]

I'm trying to use shrinky to compile the example hello world program, and am getting the following output:

 % cat main.cpp
#include "shrinky.h"

#if defined(USE_LD)
int main()
#else
void _start()
#endif
{
  shrinky();
  shrinky_puts("Hello World!");
#if defined(USE_LD)
  return 0;
#else
  asm_exit();
#endif
}

 % shrinky main.cpp
Looking for 'preprocessor' executable... 'cpp'
Cross-compile:targeting osname 'linux' instead of 'Linux'
Found header file: '/shrinky.h'
Looking for 'linker' executable... 'ld'
Analyzing source files: ['main.cpp']
Executing command: cpp main.cpp -DSHRINKY_NO_DEBUGGER_TRAP -I/usr/include/freetype2/ -I/usr/include/SDL -I/usr/local/include
1 symbols found: ['puts']
Template substitutions not matched: ['INCLUDE_RAND', 'INCLUDE_SNDFILE', 'INCLUDE_SDL', 'INCLUDE_PNG', 'UND_SYMBOLS', 'INCLUDE_FREETYPE', 'INCLUDE_OPENGL'] (7)
Wrote header file: 'shrinky.h'
Looking for 'compiler' executable... 'g++'
Looking for 'assembler' executable... 'as'
Using output file 'main' after source file 'main.cpp'.
Autodetected libraries to link against: ['c']
Looking for 'objcopy' executable... 'objcopy'
Executing command: g++ -S main.cpp -o main.S -std=c++17 -Os -ffast-math -fno-asynchronous-unwind-tables -fno-enforce-eh-specs -fno-exceptions -fno-implicit-templates -fno-rtti -fno-stack-protector -fno-threadsafe-statics -fno-use-cxa-atexit -fno-use-cxa-get-exception-ptr -fnothrow-opt -fomit-frame-pointer -funsafe-math-optimizations -fvisibility=hidden -march=core2 -Wall -mpreferred-stack-boundary=4 -DSHRINKY_NO_DEBUGGER_TRAP -I/usr/include/freetype2/ -I/usr/include/SDL -I/usr/local/include -fwhole-program
Checking for required UND symbols... None
Using shared library 'libc.so.6' instead of 'libc.so'.
5 sections in 'main.S': ['text', 'text', 'rodata', 'text', 'data']
Wrote assembler source: 'main.S'
Executing command: as main.S -o main.o
Executing command: readelf --symbols main.o
Sorted sections: 1 rodata, 1 data, 3 text
Alignment adjustment(data): 8 -> 1
Erasing function header from '_start': 1 lines
Erasing function footer after 'syscall': 4 lines
Constructed fake .bss segement: 0 bytes, one PT_LOAD sufficient
Merging headers ehdr and phdr_interp at 8 bytes.
Merging headers phdr_dynamic and dynamic at 8 bytes.
Merging headers interp and strtab at 1 bytes.
Size of headers: 292 bytes
Wrote assembler source: 'main.final.S'
Executing command: as main.final.S -o main.final.o
Executing command: ld --verbose
Wrote linker script 'main.ld'.
Executing command: ld --entry=0x400000 main.final.o -o main.bin -T main.ld
Executing command: objcopy --output-target=binary main.bin main.unprocessed
Executing command: readelf -l main.unprocessed
Traceback (most recent call last):
  File "/usr/lib/python3.10/runpy.py", line 196, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "/usr/lib/python3.10/runpy.py", line 86, in _run_code
    exec(code, run_globals)
  File "/usr/lib/python3.10/site-packages/shrinky/__main__.py", line 1443, in <module>
    sys.exit(main())
  File "/usr/lib/python3.10/site-packages/shrinky/__main__.py", line 1404, in main
    generate_binary_minimal(source_file, compiler, assembler, linker, objcopy, elfling, libraries, output_file,
  File "/usr/lib/python3.10/site-packages/shrinky/__main__.py", line 700, in generate_binary_minimal
    readelf_truncate(output_file + ".unprocessed", output_file + ".stripped")
  File "/usr/lib/python3.10/site-packages/shrinky/__main__.py", line 886, in readelf_truncate
    truncate_size = readelf_probe(src, dst, size)
  File "/usr/lib/python3.10/site-packages/shrinky/__main__.py", line 873, in readelf_probe
    info = readelf_get_info(src)
  File "/usr/lib/python3.10/site-packages/shrinky/__main__.py", line 846, in readelf_get_info
    (so, se) = run_command(["readelf", "-l", op])
  File "/usr/lib/python3.10/site-packages/shrinky/common.py", line 185, in run_command
    raise RuntimeError("command failed: %i, stderr output:\n%s" % (proc.returncode, proc_stderr))
RuntimeError: command failed: 1, stderr output:
readelf: Error: Not an ELF file - it has the wrong magic bytes at the start

/sbin/shrinky: compilation failed

It does produce two executable files, main.unprocessed and main.bin, but the first gives me a exec format error from zsh, and the latter prints a segfault.

[xyproto]

Thanks for reporting! I'll reproduce the issue.