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.
Eliminate boilerplate of having each test manually assign to `mydir` by calling
`compute_mydir` in lldbtest.py.
Differential Revision: https://reviews.llvm.org/D128077
These tests fail every 10 or so runs on Windows causing both local failures as well as buildbot failures.
Differential Revision: https://reviews.llvm.org/D111659
These two functions are doing the same thing, only one of them is
sending the packets immediately and the other "queues" them to be sent
later. The first one is better as in case of errors, the backtrace will
point straight to the place that caused them.
Modify the first method to avoid duplication, and ten standardize on it.
This commit vAttachWait in lldb-server, so --waitfor can be used on
Linux
Reviewed By: labath, clayborg
Differential Revision: https://reviews.llvm.org/D93895