Description
Description
Hello, we've noticed on Gentoo that some of our users are winding up with capstone and oprofile linked into their PHP builds "accidentally." These are used for JIT debugging, and if the configure script finds them available, it sets HAVE_CAPSTONE or HAVE_OPROFILE respectively, and prepares the build system to link with the corresponding library.
We have a big wiki page explaining why this can lead to problems, but I can sum it up in a sentence or two: sometimes, users have capstone or oprofile installed for some other reason, and not because they want to use it with PHP. If that reason changes and if the user decides to uninstall capstone (for example), doing so will break PHP if PHP was linked against capstone. Essentially the problem is that the user won't know that PHP picked up capstone or oprofile as runtime dependencies.
To fix this, the usual solution is to add explicit configure flags like --with-capstone and --with-oprofile. (Our package manager can then track the dependencies.) These features are at least nominally optional, since PHP can build without them. My main question is, does anything bad happen if someone then tries to set opcache.jit_debug to a value that uses capstone or oprofile? If not, do you foresee any other problems that I've overlooked? I've never personally debugged the JIT so I'm in over my head here.
paging @dstogov and @shqking who I see have done related work
PHP Version
git master
Operating System
No response