mirror of
https://github.com/llvm/llvm-project.git
synced 2025-05-05 21:56:06 +00:00
b15b1421bc
As the documentation states, using this is not safe in multithreaded programs, and I have traced it to a rare deadlock in some of the tests. The reason this was introduced was to be able to attach to a program from the very first instruction, where our usual mechanism of synchronization -- waiting for a file to appear -- does not work. However, this is only needed for a single test (TestGdbRemoteAttachWait) so instead of doing this everywhere, I create a bespoke solution for that single test. The solution basically consists of outsourcing the preexec_fn code to a separate (and single-threaded) shim process, which enables attaching and then executes the real program. This pattern could be generalized in case we needed to use it for other tests, but I suspect that we will not be having many tests like this. This effectively reverts commit a997a1d7fbe229433fb458bb0035b32424ecf3bd.