question regarding two security features

[Tom Henderson]

Hello, I'm writing with a question concerning whether two glibc security 
features could be optionally disabled for a specific use case.  The ns-3 
network simulator has a framework called Direct Code Execution [1, 2] 
that has been around for about ten years.  DCE allows us to load and 
simulate multiple instances of C or C++ executables and libraries that 
have been compiled as position independent code.  We link these with the 
system glibc.  Starting after glibc-2.25 or so, some vtable verification 
checks were introduced, and later, some restrictions on opening PIE 
objects were added, which blocked our usage of the system glibc for 
subsequent Linux releases (newer than Ubuntu 16.04).  We have been 
holding back on upgrades since then because of this issue.

Going forward, we can work around this by building a custom glibc (see 
sample patch at [3]) and using that within the DCE framework, but this 
approach is more heavyweight for users, so we are wondering if glibc 
would entertain the possibility of defining a link option to disable 
these features?

- Tom

[1] https://hal.inria.fr/hal-00880870/document
[2] https://github.com/direct-code-execution
[3] 
https://github.com/ParthPratim/ns-3-dce/commit/790b70674061eb11e94d7cf49d90b0373016178f