[Openmp-commits] [PATCH] D142008: [libomptarget] Delay recursive shared library registrations until offload RTLs are loaded

[Jon Chesterfield via Phabricator via Openmp-commits]

JonChesterfield added a comment.

Spent way too long thinking about this and ended up reading the glibc source.

I don't think we want reference counting, more locks or delayed registration. I think we want to move the plugin initialisation to the end of the libomptarget constructor and delete the once_flag guarding it.

The amdgpu plugin will load HSA which will load libomptarget. So our global ctor needs to be reentrant, that's why reference counting it looks like a fix. But we don't need a reference count, just a nop on the second call, and it doesn't need a lock because we're already holding one via glibc.

Then constructors in user code happen sometime after libomptarget is constructed and will be fine.

I haven't implemented this, just thought it through. Joseph is testing the idea now I think.


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https://reviews.llvm.org/D142008