OpenEuphoria

But you did not ask it to solve the recurring "Can't install phix" posts?

why does ./p64 segfault but /usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2 ./p64 work?

There could be a number of reasons why running ./p64 might cause a segmentation fault, but one possible reason is that the program was compiled for a different architecture than the one you are currently running it on. The /usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2 file is a dynamic linker that is used to load and run programs on Linux systems. When you run the program with this dynamic linker, it is able to properly load the program and its dependencies, which is why it works. However, when you run the program directly with ./p64, the system is unable to properly load the program, which can cause a segmentation fault.

but ./p64 should invoke /usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2 anyway

Yes, that's correct. In most cases, running ./p64 should automatically invoke the dynamic linker, /usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2, behind the scenes. This is because the ELF (Executable and Linkable Format) file format, which is used for executables on Linux systems, specifies that the dynamic linker should be run automatically when an ELF executable is executed.

so why does it segfault?

As I mentioned earlier, there could be a number of reasons why running ./p64 might cause a segmentation fault. Some possible reasons include:

• The program was compiled for a different architecture than the one you are currently running it on.
• The program is trying to access memory that it is not allowed to access, either because the memory is protected or because the program has a bug that is causing it to access invalid memory.
• The program is relying on a shared library that is not installed on your system, or that is installed in a different location than the program expects.
• The program is using an instruction that is not supported by your CPU, or that is not implemented in the same way on your CPU as it is on the CPU that the program was compiled for.

It's difficult to say exactly why ./p64 is causing a segmentation fault without more information about the program and the environment it is being run in. To troubleshoot the issue, you could try running the program under a debugger to see where it is crashing, and you could also try running the program on a different system to see if the problem persists.

but none of those can possibly be the cause if it works when run the second way

That's correct. If running the program with the dynamic linker, /usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2, works, then it is unlikely that the problem is caused by any of the issues I listed earlier (e.g. the program being compiled for the wrong architecture, or the program using an instruction that is not supported by your CPU). However, it is still possible that the problem is caused by one of those issues. For example, if the program is dynamically linked to a shared library that is not installed on your system, then running the program with the dynamic linker might allow the program to run because the linker is able to find and load the necessary library.

but the shared library must exist if it works the second way

Yes, that's correct. If the program is dynamically linked to a shared library, and if running the program with the dynamic linker works, then it must mean that the necessary library is installed on your system. In this case, the problem is not likely to be caused by a missing shared library.