ASSERT pend_unit_size does not have AVX_ALIGNMENT on processor with AVX

Created by: petervbraun

Note this is different than the similarly titled issue because my processor does have AVX. I am using the most recent source code. The assert is in core/unix/signal.c:532 IF_LINUX(IF_X86(ASSERT(!YMM_ENABLED() || ALIGNED(pend_unit_size, AVX_ALIGNMENT)))); My machine is linux, is x86, and does have YMM_ENABLED. This fails because on my machine pend_unit_size=3272 which is not a multiple of 64. I also find

Sizeof(sigpending_t)=1344
Signal_frame_extra_size(true)=2760
-sizeof(kernel_xstate_t)=-832

Where pend_unit_size = Sizeof(sigpending_t) + Signal_frame_extra_size(true) + -sizeof(kernel_xstate_t) and signal_frame_extra_size(true) = xstate_size + (AVX_ALIGNMENT – 4). The comments on signal_frame_extra_size() from signal_linux_x86.c seem to indicate that the second part, (AVX_ALIGNMENT – 4), is supposed to ensure alignment. If I change that instead to either (AVX_ALIGNMENT – 12) or (AVX_ALIGNMENT + 52) the assert statement succeeds. Is this a correct modification?