Refactor C/Fortran interfaces and enforce non-executable stack #125
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• Added the linker flag "-Wl,-z,noexecstack" in Makefile_gnu to disable executable stacks for improved security. • In src/polychord/interfaces.F90: move all functions defined internally in contains functions to module-level definitions with module-level variables. This fixes the bug found in #124 which has arisen for glibc 2.41 which does not allow executable stack calls
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OK, an hours marathon vibing with o3-mini high eventually revealed the problem to be a combination of needing to add some linker flags, and a re-write of the interfaces so that it does not define functions within a function's contains section.
Cool, nice to see that I wasn't too far off with my link from #124, which addresses the issue with nested functions.
This PR indeed fixes my install issue, and python run_pypolychord.py now runs without issue.
However, since this so far only modifies interfaces.F90, but I stumbled upon that little X in both interfaces.o and maximiser.o (see the last paragraph in my first post in #124), I dug a bit further. There are indeed nested functions in maximiser.F90 as well, and when adding settings.maximise = True to run_pypolychord.py, then it will segfault the moment it starts trying to maximise the likelihood. So I guess the same needs to be done for maximiser.F90.
• Added the linker flag "-Wl,-z,noexecstack" in Makefile_gnu to disable executable stacks for improved security.
• In src/polychord/interfaces.F90:
move all functions defined internally in contains functions to module-level definitions with module-level variables.
This fixes the bug found in #124 which has arisen for glibc 2.41 which does not allow executable stack calls