Hi, everyone. I'm considering running some effort to improve protocol-level compatibility between LLDB and GDB. I'd like to hear if there's interest in such patches being accepted into LLDB.
My goal would be to make it possible to use LLDB to connect to gdbserver (and other servers implementing the same protocol), and to be able to use full set of debugger's features while doing that. Ideally, also connecting to lldb-server from GDB would be supported too. I think the first blocker towards this project are existing implementation bugs in LLDB. For example, the vFile implementation is documented as using incorrect data encoding and open flags. This is not something that can be trivially fixed without breaking compatibility between different versions of LLDB. My current idea would be to add some logic to distinguish the current (i.e. 'old') versions of LLDB from GDB, and to have new versions of LLDB indicate GDB protocol fixes via qSupported. For example, unless I'm mistaken 'QThreadSuffixSupported' is purely an LLDB extension. Let's say we implement GDB-compatible vFile packets as 'gdb-compat:vFile' feature. The client would: 1. Send 'gdb-compat:vFile' in qSupported to indicate that it's ready to use correct GDB-style packets. 2. Check for server's qSupported response. Now: - if it contains 'gdb-compat:vFile+', then we're dealing with new version of lldb-server and we use gdb-style vFile packets, - otherwise, if it contains 'QThreadSuffixSupported+', then we're dealing with old version of lldb-server and we use lldb-style vFile packets, - otherwise, we assume we're dealing with real GDB, and we use gdb-style packets. On the server-side, we would similarly check for 'gdb-compat:vFile+' in client's qSupported, and for the call to 'QThreadSuffixSupported' to determine whether we're dealing with GDB or LLDB client. What do you think? -- Best regards, Michał Górny _______________________________________________ lldb-dev mailing list lldb-dev@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-dev
