[Lldb-commits] [lldb] Reland "[lldb][RPC] Upstream lldb-rpc-gen tool" (#146969)" Attempt 2 (PR #148996)

[Chelsea Cassanova via lldb-commits]

chelcassanova wrote:

@mstorsjo @vvereschaka I can try reproducing the issue with the universal binaries on macOS, but I don't currently have a setup to try reproducing the issue with cross-compiling so I think I'll need some help there.

I noted this in https://github.com/llvm/llvm-project/issues/150454, but from the error there:
```
cd /home/runner/work/llvm-mingw/llvm-mingw/llvm-project/llvm/build-thinlto-withclang-pgo-aarch64-linux-gnu && /usr/local/bin/cmake -E make_directory /home/runner/work/llvm-mingw/llvm-mingw/llvm-project/llvm/build-thinlto-withclang-pgo-aarch64-linux-gnu/tools/lldb/tools/lldb-rpc/generated && /usr/local/bin/cmake -E make_directory /home/runner/work/llvm-mingw/llvm-mingw/llvm-project/llvm/build-thinlto-withclang-pgo-aarch64-linux-gnu/tools/lldb/tools/lldb-rpc/generated/server && -p /home/runner/work/llvm-mingw/llvm-mingw/llvm-project/llvm/build-thinlto-withclang-pgo-aarch64-linux-gnu --output-dir=/home/runner/work/llvm-mingw/llvm-mingw/llvm-project/llvm/build-thinlto-withclang-pgo-aarch64-linux-gnu/tools/lldb/tools/lldb-rpc/generated --extra-arg="-USWIG" /home/runner/work/llvm-mingw/llvm-mingw/llvm-project/lldb/include/lldb/API/SBAddress.h /home/runner/work/llvm-mingw/llvm-mingw/llvm-project/lldb/include/lldb/API/SBAddressRange.h [...]
/bin/sh: 1: -p: not found
```
This corresponds to this cmake command:
```
  COMMAND ${LLDB_RPC_GEN_EXE}
    -p ${CMAKE_BINARY_DIR}
    --output-dir=${lldb_rpc_generated_dir}
    ${sysroot_arg}
    --extra-arg="-USWIG"
    ${api_headers}
```

`/bin/sh: 1: -p: not found`. From this, my guess is that the LLDB_RPC_GEN_EXE variable is not being set correctly, and this command is then attempted to be run as though the command were `-p` instead of `lldb-rpc-gen`.

https://github.com/llvm/llvm-project/pull/148996