Hi all, Last night I opened two pull requests to begin fixing the CallWithMRs code path on x86_64 and aarch32. syscall_stub_gen.py couldn't generate x86_64 stubs for the CallWithMRs / non-IPCBuffer path. That didn't surprise me too much, as x86_64 support is relatively new. Then I discovered that libsel4 *always* [1] uses the IPCBuffer path. Hrm. Changing that prompted a quick fix to aarch32's apparently unused, long since even built CallWithMRs. (Similar fixes might be needed in some of the other functions.) The test suite failed with it on aarch32, which I could poke at in more depth, but it worked fine for x86_64. So… what's the status of the *WithMRs functions? Based on my understanding of the source (particularly the new helper functions) and assembly output, they're destined for the chopping block, right? Thanks, Jeff [1] hard coded --buffer parameter to syscall_stub_gen.py in libsel4/Makefile, since late 2015